@article{hackman_cook_strahm_carter_woodley_garcia_albaugh_rubilar_campoe_2024, title={<i>Pinus</i><i> taeda</i> carryover phosphorus availability on the lower Atlantic Coastal Plain}, volume={555}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2024.121701}, abstractNote={Phosphorus (P) fertilizer that remains in the soil after harvest and into the subsequent rotation is referred to as carryover P. Carryover P is not well understood in loblolly pine (P. taeda) silviculture, especially on highly P responsive sites, where this effect could potentially have the greatest benefit to land managers. Our study aims to determine the duration of the P carryover effect and the magnitude of response to soil P as it relates to previously applied P fertilizer rates from the previous rotation. To address this knowledge gap, we studied two highly weathered sites on the lower Atlantic coastal plain: a somewhat poorly drained Spodosol and a poorly drained Alfisol over three years from pre- to post-harvest. Two years post planting, carryover fertilizer treatments resulted in a 13% increase in height for the 121 kg P ha-1, a 15% for the 81 kg P ha-1, and a 17% increase for the fertilized 40 + 45 kg P ha-1 treatments compared to the control for the Alfisol. Spodosols appeared to respond to any additional fertilization compared to the control group regardless of rate. Importantly, we found that O horizon mass and P content from the first rotation, approximately seven years before harvest, exhibited a positive linear relationship with one-year-old heights in the Spodosol and one- and two-year-old heights in the Alfisol. These findings shed light on the importance of the O horizon characteristics and its potential as an indicator for tree growth in subsequent rotations.}, journal={FOREST ECOLOGY AND MANAGEMENT}, publisher={Elsevier BV}, author={Hackman, Jacob and Cook, Rachel and Strahm, Brian and Carter, David and Woodley, Alex and Garcia, Kevin and Albaugh, Timothy and Rubilar, Rafael and Campoe, Otavio}, year={2024}, month={Mar} }
 @article{house_wynne_thomas_cook_carter_mullekom_rakestraw_schroeder_2024, title={Effects of establishment fertilization on Landsat-assessed leaf area development of loblolly pine stands}, volume={556}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2023.121655}, abstractNote={Loblolly pine (Pinus taeda L.) plantations in the southeastern United States are among the world's most intensively managed forest plantations. Under intensive management, a common practice is fertilizing at establishment. The objective of this study was to investigate the effect of establishment fertilization on leaf area development of loblolly pine plantation stands (n = 3997) over 16 years compared to stands that did not receive nutrient additions at planting. Leaf area index (LAI) is a meaningful biophysical indicator of vigor and an important functional and structural element of a planted stand. The study area was stratified by plant hardiness zone to account for climatic differences and soil type (texture and drainage class), using the Cooperative Research in Forest Fertilization (CRIFF) groupings. LAI was estimated from Landsat imagery to create trajectories of mean stand LAI over 16 years. Establishment fertilization, on average, (1) increased stand LAI beginning at year two, with a peak at years six and seven, and (2) decreased the time required for a stand to reach a winter LAI of 1.5 by almost two years. Fertilization responses varied by climate zone and soil drainage class, where the warmest zones benefited the most, particularly in poorly drained soils. Past year 10, the differences in LAI between fertilized and unfertilized stands were not practically important. Using Landsat data in a cloud-computing environment, we demonstrated the benefits of establishment fertilization to stand LAI development using a large sample over the native range of loblolly pine.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={House, Matthew N. and Wynne, Randolph H. and Thomas, Valerie A. and Cook, Rachel L. and Carter, David R. and Mullekom, Jennifer H. Van and Rakestraw, Jim and Schroeder, Todd A.}, year={2024}, month={Mar} }
 @article{cook_fox_allen_cohrs_ribas-costa_trlica_ricker_carter_rubilar_campoe_et al._2024, title={Forest soil classification for intensive pine plantation management: "Site Productivity Optimization for Trees" system}, volume={556}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2024.121732}, abstractNote={Forest productivity and response to silvicultural treatments are dependent on inherent site resource availability and limitations. Trees have deeper rooting profiles than agronomic crops, so evaluating the impacts of soils, geology, and physiographic province on forest productivity can help guide silvicultural management decisions in southern pine plantations. Here, we describe the Forest Productivity Cooperative’s “Site Productivity Optimization for Trees” (SPOT) system which includes: texture, depth to increase in clay content, drainage class, soil modifiers (i.e., surface attributes, mineralogy, and additional limitations such as root restrictions), geologic formations, and physiographic province. We quantified the total area for each SPOT code in the native range of loblolly pine (Pinus taeda L.), the region’s most commercially important species, and used a remotely-sensed layer to quantify SPOT code areas in managed southern pine (approximately 14 million ha). The most common SPOT code in the native range is also the most planted, a B2WekoGgPD (fine loamy, shallow depth to increase in clay, well-drained, eroded, kaolinitic, granitic, Piedmont soil), spanning 1.1 million ha total, but only 12% in managed southern pine. However, the SPOT code with the greatest percentage of managed southern pine (61%; a D4PoioAmAF, spodic, deep to increase in clay, siliceous, middle Atlantic Coastal Plain, Flatwoods soil) was the 20th most common in the native range with 474,662 ha. We used machine learning and data from decades of “Regionwide” trials to assess the variable importance of SPOT constituents, climate, planting year, and N rate on site index (base age 25 years) and found that planting year was the most important variable, showing an increase of 17 cm site index per year since 1970, followed by maximum vapor pressure deficit, and precipitation. Geology was the top-ranking SPOT variable to explain site index followed by physiographic province. The Regionwide trials represent 72 unique SPOT codes (out of over 10,000 possible in the pine plantations) and approximately one million ha (or about 7% of all soils identified as supporting managed pine). To extrapolate site index values outside of the unique soil and geologic conditions empirically represented, we created a predictive model with an R2 of 0.79 and an RMSE of 1.38 m from SPOT codes alone. With this extrapolation, the Regionwide data predicts 10.5 million ha, or 74%, of all soils under loblolly pine management in its native range. Overall, this system will allow managers to assess their current site productivity, and recommend silvicultural treatments, thus, providing a framework to optimize forest productivity in pine plantations in the southeastern US.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Cook, Rachel and Fox, Thomas R. and Allen, Howard Lee and Cohrs, Chris W. and Ribas-Costa, Vicent and Trlica, Andrew and Ricker, Matthew and Carter, David R. and Rubilar, Rafael and Campoe, Otavio and et al.}, year={2024}, month={Mar} }
 @article{hackman_woodley_carter_strahm_averill_vilgalys_garcia_cook_2024, title={Fungal biomass and ectomycorrhizal community assessment of phosphorus responsive <i>Pinus taeda</i> plantations}, volume={5}, ISSN={["2673-6128"]}, DOI={10.3389/ffunb.2024.1401427}, abstractNote={Ectomycorrhizal fungi and non-ectomycorrhizal fungi are responsive to changes in environmental and nutrient availabilities. Although many species of ectomycorrhizas are known to enhance the uptake of phosphorus and other nutrients for Pinus taeda , it is not understood how to optimize these communities to have tangible effects on plantation silviculture and P use efficiency. The first step of this process is the identification of native fungi present in the system that are associated with P. taeda and influence P uptake efficiency. We used sand-filled mesh bags baited with finely ground apatite to sample ectomycorrhizal and non-ectomycorrhizal fungi associated with the rhizosphere of P-responsive P. taeda under several field conditions. Mesh bags were assessed for biomass accumulation over three years using a single three-month burial period pre-harvest and three six-month burial periods post-planting. Amplicon sequencing assessed ectomycorrhizal and non-ectomycorrhizal communities between phosphorus treatments, sites, mesh bags, and the rhizosphere of actively growing P. taeda in the field. We found biomass accumulation within the mesh bags was inversely related to increasing phosphorus fertilization (carryover) rates from pre-harvest to post-planting. Up to 25% increases in total biomass within the bags were observed for bags baited with P. Taxonomic richness was highest in Alfisol soils treated with phosphorus from the previous rotation and lowest in the Spodosol regardless of phosphorus treatment.}, journal={FRONTIERS IN FUNGAL BIOLOGY}, author={Hackman, Jacob and Woodley, Alex and Carter, David and Strahm, Brian and Averill, Collin and Vilgalys, Rytas and Garcia, Kevin and Cook, Rachel}, year={2024}, month={May} }
 @article{ribas-costa_cook_gaston_2024, title={Modeling structural traits of Aleppo pine (<i>Pinus halepensis</i> Mill.) forests with low-density LiDAR}, volume={57}, ISSN={["2279-7254"]}, DOI={10.1080/22797254.2024.2344569}, number={1}, journal={EUROPEAN JOURNAL OF REMOTE SENSING}, author={Ribas-Costa, Vicent A. and Cook, Rachel L. and Gaston, Aitor}, year={2024}, month={Dec} }
 @article{puls_cook_baker_rakestraw_trlica_2024, title={Modeling wood product carbon flows in southern us pine plantations: implications for carbon storage}, volume={19}, ISSN={["1750-0680"]}, DOI={10.1186/s13021-024-00254-4}, abstractNote={Abstract}, number={1}, journal={CARBON BALANCE AND MANAGEMENT}, author={Puls, Sarah J. and Cook, Rachel L. and Baker, Justin S. and Rakestraw, James L. and Trlica, Andrew}, year={2024}, month={Feb} }
 @article{nilsson_nilsson_nasholm_cook_hjelm_2024, title={Nitrogen uptake, retranslocation and potential N<sub>2</sub>-fixation in Scots pine and Norway spruce seedlings}, volume={2}, ISSN={["1573-5095"]}, DOI={10.1007/s11056-024-10032-2}, journal={NEW FORESTS}, author={Nilsson, Oscar and Nilsson, Urban and Nasholm, Torgny and Cook, Rachel and Hjelm, Karin}, year={2024}, month={Feb} }
 @article{raigosa-garcia_rathbun_cook_baker_corrao_sumnall_2024, title={Rethinking Productivity Evaluation in Precision Forestry through Dominant Height and Site Index Measurements Using Aerial Laser Scanning LiDAR Data}, volume={15}, ISSN={["1999-4907"]}, DOI={10.3390/f15061002}, abstractNote={Optimizing forest plantation management has become imperative due to increasing forest product demand, higher fertilization and management costs, declining land availability, increased competition for land use, and the growing demands for carbon sequestration. Precision forestry refers to the ability to use data acquired with technology to support the forest management decision-making process. LiDAR can be used to assess forest metrics such as tree height, topographical position, soil surface attributes, and their combined effects on individual tree growth. LiDAR opens the door to precision silviculture applied at the tree level and can inform precise treatments such as fertilization, thinning, and herbicide application for individual trees. This study uses ALS LiDAR and other ancillary data to assess the effect of scale (i.e., stand, soil type, and microtopography) on dominant height and site index measures within loblolly pine plantations across the southeastern United States. This study shows differences in dominant height and site index across soil types, with even greater differences observed when the interactions of microtopography were considered. These results highlight how precision forestry may provide a unique opportunity for assessing soil and microtopographic information to optimize resource allocation and forest management at an individual tree scale in a scarce higher-priced fertilizer scenario.}, number={6}, journal={FORESTS}, author={Raigosa-Garcia, Ivan and Rathbun, Leah C. and Cook, Rachel L. and Baker, Justin S. and Corrao, Mark V. and Sumnall, Matthew J.}, year={2024}, month={Jun} }
 @article{rose_dellinger_larmour_polishook_higuita-aguirre_dutta_cook_zimmermann_garcia_2024, title={The ectomycorrhizal fungus <i>Paxillus ammoniavirescens</i> influences the effects of salinity on loblolly pine in response to potassium availability}, volume={26}, ISSN={["1462-2920"]}, url={https://doi.org/10.1111/1462-2920.16597}, DOI={10.1111/1462-2920.16597}, abstractNote={Abstract}, number={3}, journal={ENVIRONMENTAL MICROBIOLOGY}, author={Rose, Benjamin D. and Dellinger, Marissa A. and Larmour, Clancy P. and Polishook, Mira I. and Higuita-Aguirre, Maria I. and Dutta, Summi and Cook, Rachel L. and Zimmermann, Sabine D. and Garcia, Kevin}, year={2024}, month={Mar} }
 @article{hackman_cook_strahm_carter_woodley_garcia_2024, title={Using microdialysis to assess soil diffusive P and translocated sap flow P concentrations in Southern <i>Pinus taeda</i> plantations}, volume={1}, ISSN={["1573-5036"]}, DOI={10.1007/s11104-023-06468-8}, journal={PLANT AND SOIL}, author={Hackman, Jacob and Cook, Rachel and Strahm, Brian and Carter, David and Woodley, Alex and Garcia, Kevin}, year={2024}, month={Jan} }
 @article{sumnall_albaugh_carter_cook_hession_campoe_rubilar_wynne_thomas_2023, title={Estimation of individual stem volume and diameter from segmented UAV laser scanning datasets in Pinus taeda L. plantations}, volume={44}, ISSN={["1366-5901"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85148453201&partnerID=MN8TOARS}, DOI={10.1080/01431161.2022.2161853}, abstractNote={ABSTRACT The competitive neighbourhood surrounding an individual tree can have a significant influence on its diameter at breast height (DBH) and individual tree stem volume (SV). Distance dependent competition index metrics are rarely recorded in traditional field campaigns because they are laborious to collect and are spatially limited. Remote sensing data could overcome these limitations while providing estimation of forest attributes over a large area. We used unoccupied aerial vehicle laser scanning data to delineate individual tree crowns (ITCs) and calculated crown size and distance-dependent competition indices to estimate DBH and SV. We contrasted two methods: (i) Random Forest (RF) and (ii) backwards-stepwise, linear multiple regression (LMR). We utilized an existing experiment in Pinus taeda L. plantations including multiple planting densities, genotypes and silvicultural levels. While the tree planting density did affect the correct delineation of ITCs, between 61% and 99% (mean 86%) were correctly linked to the planting location. The most accurate RF and LMR models all included metrics related to ITC size and competitive neighbourhood. The DBH estimates from RF and LMR were similar: RMSE 3.05 and 3.13 cm (R2 0.64 and 0.62), respectively. Estimates of SV from RF were slightly better than for LMR: RMSE 0.06 and 0.07 m3 (R2 0.77 and 0.70), respectively. Our results provide evidence that ITC size and competition index metrics may improve DBH and SV estimation accuracy when analysing laser-scanning data. The ability to provide accurate, and near-complete, forest inventories holds a great deal of potential for forest management planning.}, number={1}, journal={INTERNATIONAL JOURNAL OF REMOTE SENSING}, author={Sumnall, Matthew J. J. and Albaugh, Timothy J. J. and Carter, David R. R. and Cook, Rachel L. L. and Hession, W. Cully and Campoe, Otavio C. and Rubilar, Rafael A. A. and Wynne, Randolph H. H. and Thomas, Valerie A. A.}, year={2023}, month={Jan}, pages={217–247} }
 @article{rubilar_bozo_albaugh_cook_campoe_carter_allen_alvarez_pincheira_zapata_2023, title={Rotation-age effects of subsoiling, fertilization, and weed control on radiata pine growth at sites with contrasting soil physical, nutrient, and water limitations}, volume={544}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2023.121213}, abstractNote={Although short- and medium-term responses to early silvicultural treatments have been documented, few studies show productivity gains or losses throughout a rotation across a range of soil types and resource availability. We evaluated the rotation length productivity responses of radiata pine to subsoiling, fertilization, and weed control in dry sand (DS), red clay (RC), and recent volcanic ash (RV) soils representing a gradient of physical, nutrient, and water limitations. Stands were planted in 2000 in a split-plot factorial design, with soil preparation (subsoiling vs. shovel planting) as the main plot and fertilization at planting (B only vs. NPKB) and weed control (none vs. 2-year banded application) as factorial randomized treatment plots within the main plots. Annual diameter at breast height, height, survival, and cumulative volume responses were measured. The rotation-age results for cumulative volume showed that early gains from weed control were maintained through at least 15 years of age. At rotation age, weed control increased the cumulative volume at the DS site (56 m3/ha, 20% gain), and the response over time was maintained at the RC site (28 m3/ha, 8% gain), whereas the volume was reduced at the RV site (-36 m3/ha, 7% loss). Fertilization resulted in the greatest response at the RC site (29 m3/ha, 8% gain); there were small responses at the DS site (5 m3/ha, 2% gain) and negative responses at the RV site (-18 m3/ha, 4% loss). Interestingly, subsoiling resulted in null or negative responses at all sites, and negative effects increased over time, with volume responses ranging from −4 m3/ha (1% loss) and −27 m3/ha (7% loss) at the DS and RC sites, respectively, to −116 m3/ha (21% loss) at the RV site. Carrying capacity was reached at mid-rotation at the RV site and resulted in negative treatment effects at rotation age, suggesting the need for thinning or a younger harvest age at this site. Given the negative or null effects of soil preparation, a better understanding is needed for how this silvicultural treatment is affected by soil type and soil strength.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Rubilar, Rafael and Bozo, Daniel and Albaugh, Timothy and Cook, Rachel and Campoe, Otavio and Carter, David and Allen, H. Lee and Alvarez, Jose and Pincheira, Matias and Zapata, Alvaro}, year={2023}, month={Sep} }
 @article{the first decade of tamm reviews_2023, volume={534}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85148723664&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2023.120875}, journal={Forest Ecology and Management}, year={2023} }
 @article{ritz_thomas_wynne_green_schroeder_albaugh_burkhart_carter_cook_campoe_et al._2022, title={Assessing the utility of NAIP digital aerial photogrammetric point clouds for estimating canopy height of managed loblolly pine plantations in the southeastern United States}, volume={113}, ISSN={["1872-826X"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85137622876&partnerID=MN8TOARS}, DOI={10.1016/j.jag.2022.103012}, abstractNote={Remote sensing offers many advantages to supplement traditional, ground-based forest measurements, such as limiting time in the field and fast spatial coverage. Data from airborne laser scanning (lidar) have provided accurate estimates of forest height, where, and when available. However, lidar is expensive to collect, and wall-to-wall coverage in the United States is lacking. Recent studies have investigated whether point clouds derived from digital aerial photogrammetry (DAP) can supplement lidar data for estimating forest height due to DAP's lower costs and more frequent acquisitions. We estimated forest heights using point clouds derived from the National Agricultural Imagery Program (NAIP) DAP program in the United States to create a predicted height map for managed loblolly pine stands. For 534 plots in Virginia and North Carolina, with stand age ranging from 1 year to 42 years old, field-collected canopy heights were regressed against the 90th percentile of heights derived from NAIP point clouds. Model performance was good, with an R2 of 0.93 and an RMSE of 1.44 m. However, heights in recent heavily thinned stands were consistently underestimated, likely due to between-row shadowing leading to a poor photogrammetric solution. The model was applied to non-thinned evergreen areas in Virginia, North Carolina, and Tennessee to produce a multi-state 5 m × 5 m canopy height map. NAIP-derived point clouds are a viable means of predicting canopy height in southern pine stands that have not been thinned recently.}, journal={INTERNATIONAL JOURNAL OF APPLIED EARTH OBSERVATION AND GEOINFORMATION}, author={Ritz, Alison L. and Thomas, Valerie A. and Wynne, Randolph H. and Green, P. Corey and Schroeder, Todd A. and Albaugh, Timothy J. and Burkhart, Harold E. and Carter, David R. and Cook, Rachel L. and Campoe, Otavio C. and et al.}, year={2022}, month={Sep} }
 @article{rojas_campoe_albaugh_cook_rubilar_carter_alvares_2022, title={Carbon Stock and Fluxes are Affected by Pinus Taeda Genetic Variation and Stand Density}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85131110664&partnerID=MN8TOARS}, journal={SSRN}, author={Rojas, G. and Campoe, O.C. and Albaugh, T.J. and Cook, R.L. and Rubilar, R.A. and Carter, D.R. and Alvares, C.A.}, year={2022} }
 @article{carter_albaugh_sumnall_grossman_campoe_cook_rubilar_maier_coates_defeo_et al._2022, title={Crown Complementarity Rather than Crown Selection Contributes to Stem Complementarity in Genetic Mixtures of Pinus Taeda L}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85144906957&partnerID=MN8TOARS}, journal={SSRN}, author={Carter, D.R. and Albaugh, T.J. and Sumnall, M. and Grossman, J.J. and Campoe, O.C. and Cook, R.L. and Rubilar, R.A. and Maier, C.A. and Coates, T.A. and DeFeo, J. and et al.}, year={2022} }
 @article{sumnall_albaugh_carter_cook_hession_campoe_rubilar_wynne_thomas_2022, title={Effect of varied unmanned aerial vehicle laser scanning pulse density on accurately quantifying forest structure}, volume={43}, ISSN={["1366-5901"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85123921158&partnerID=MN8TOARS}, DOI={10.1080/01431161.2021.2023229}, abstractNote={ABSTRACT Airborne laser scanning (ALS) is increasingly used to estimate various forest characteristics. Technological improvements in unmanned aerial vehicles (UAVs) and drone laser scanning (DLS) sensors have permitted the acquisition of high pulse density datasets. There is an assumption that higher pulse densities yield greater accuracies in estimating forest characteristics. In this study, we investigated the effect of pulse density (.25, .5, 1, 5, 10, 50, 100 and 300 pulses m−2) on the ability to delineate individual tree crowns (ITCs) and estimate ITC height and crown horizontal diameter, in addition to plot-level leaf area index (LAI). The current study took place in an experimentally varied Pinus taeda L. forest, which included three stem densities: (i) 618; (ii) 1236; and (iii) 1853 trees per hectare (TPH). ITCs were classified directly from the DLS point cloud for each of the pulse densities. The correct delineation of ITCs relative to field tree-coordinates was relatively consistent (±5%) for pulse densities of 5 to 300 pulses m−2. ITC delineation accuracy decreased with lower pulse densities. Planting stem density did impact ITC delineation accuracy. Higher pulse densities, plots with 618 TPH correctly classified ~88% of ITCs, and plots with the 1853 TPH correctly classified ~50% of ITCs. Estimates of tree height were largely unaffected by changes in tree density. Root mean square error (RMSE) for tree height varied from .5 to 2.5 m at pulse densities of 300 to .25 pulses m−2, respectively. Estimates of crown horizontal diameter varied with regard to both pulse and stem density from 1.2 (300 ppm−2 and 1853 TPH) to 4.2 m (.25 ppm−2 and 618 TPH). RMSE varied among stem densities from .6 to 1.2 m as pulse density decreased. There was significant difference in ITC delineation accuracy, particularly when considering stem density, and the estimates of tree height and crown horizontal diameter among the DLS pulse densities used. The accuracy of predicted LAI was largely unaffected by changes in pulse density, when pulse density was above .5 pulses m−2. There was little or no difference in estimates of LAI at these pulse densities. Our results suggest that low-density DLS data may be capable of estimating plot-level forest metrics reliably in some situations, however once the analysis scale is reduced to the individual-tree-level, the influence of pulse density is more substantial. The results here provide guidance to forest managers who must balance metric estimation accuracy and price when planning new ALS or DLS acquisitions.}, number={2}, journal={INTERNATIONAL JOURNAL OF REMOTE SENSING}, author={Sumnall, Matthew J. and Albaugh, Timothy J. and Carter, David R. and Cook, Rachel L. and Hession, W. Cully and Campoe, Otavio C. and Rubilar, Rafael A. and Wynne, Randolph H. and Thomas, Valerie A.}, year={2022}, month={Jan}, pages={721–750} }
 @article{hackman_ozyhar_chien_hilty_woodley_cook_2022, title={Evaluation of synthetic hydroxyapatite as a potential phosphorus fertilizer for application in Forest plantations}, volume={18}, ISSN={["2158-0715"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85136474133&partnerID=MN8TOARS}, DOI={10.1080/21580103.2022.2115149}, abstractNote={Abstract Synthetic hydroxyapatite (HA) was compared against triple superphosphate (TSP) and two unprocessed phosphate rocks (PR1, PR2) to (1) quantify and assess a synthetic lamellar structured-HA for its solubility and diffusiveness under acidic, sandy, soil conditions, (2) Evaluate synthetic lamellar structured-HA as a phosphorus early rotation fertilizer for Eucalyptus saplings. Soil incubation experiments verified that HA released more diffusive phosphorus into the soil than non-synthetic phosphate rock and had similar amounts of diffusive phosphorus as TSP. The solubility of HA at pH 3 and pH 6 was higher than that of raw ground phosphate rocks (apatites). Total dry-matter yield (DMY) and shoot-length of Eucalyptus seedlings grown for 154 days in acid soil (pH 4.9) were increased significantly by the application of HA compared to the control, PR2, and mixed (HA + PR2). The lack of a DMY response using TSP indicates that phosphorus may not have been the limiting factor. However, considering TSP and HA had similar solubilities and released diffusive phosphorus at similar levels, the only variable we failed to control for was the CaCO3 provided by the HA and not the TSP. Further experimentation is needed to confirm this hypothesis. Overall, HA is a promising candidate to supplement traditional phosphorus fertilizers for acidic sandy Eucalyptus silviculture.}, number={3}, journal={FOREST SCIENCE AND TECHNOLOGY}, author={Hackman, Jacob and Ozyhar, Tomasz and Chien, S. H. and Hilty, Florentine and Woodley, Alex and Cook, Rachel L.}, year={2022}, month={Jul}, pages={127–134} }
 @article{albaugh_carter_cook_campoe_rubilar_creighton_2022, title={Improving Pinus taeda site index from rotation to rotation with silvicultural treatments}, volume={526}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85139855986&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2022.120581}, abstractNote={We wanted to improve site index using fertilizer applications and planting density at a site with a site index of 16.8 m at a base age of 25 years. We installed a randomized complete block study in the Virginia Piedmont with three replications of three levels of fertilization (cumulative elemental nitrogen and phosphorous amounts of 0 and 45, 309 and 73, and 787 and 129 kg ha−1, respectively) and two levels of planting density (896 and 1793 trees ha−1). We measured the stand 15 times and completed our analysis after age 22 measurements. Fertilization and planting density did not affect site index and there was no planting density by fertilization interaction. Fertilizer significantly increased stem diameter and basal area but did not affect dominant height. Low planting density resulted in significantly larger diameter trees with longer crowns, but with less basal area and stand scale production than the high planting density. However, site index in all treatments improved to 24.2 m, a 7.4 m increase from one rotation to the next. We attributed the increase in site index to adding the primary limiting resource (phosphorous), better competition control, genetics and growing environment. Silvicultural inputs and environmental conditions influence site index and estimates of productivity (e.g. m3 ha−1 yr−1) may be more useful.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Albaugh, Timothy J. and Carter, David R. and Cook, Rachel L. and Campoe, Otavio C. and Rubilar, Rafael A. and Creighton, Jerre L.}, year={2022}, month={Dec} }
 @article{kinane_montes_zapata_bullock_cook_mishra_2022, title={Influence of environmental variables on leaf area index in loblolly pine plantations}, volume={523}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85137157938&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2022.120445}, abstractNote={• We modeled leaf area index development in Pinus taeda plantations. • Environmental modifiers were incorporated to account for growth variations. • Monthly maximum temperature and monthly excess water were influential growth modifiers. • Peak LAI growth can be satisfied by a range of conditions. The productivity of even-aged forest stands varies from one year to the next as a function of canopy size and its interaction with the effective radiation used for photosynthesis. To characterize this relation, ecologists use leaf area index (LAI), a metric that serves as an indicator of the photosynthetic capacity on a given site. In this research, we proposed a model describing leaf area index dynamics in loblolly pine plantations growing in the southeastern United States. The model implements a delayed differential equation using periodic coefficients that enforce the seasonality in resource availability. The equation was further expanded to accommodate climatic variables to evaluate their contribution in reducing the observed variability. The proposed model uses environmental modifiers to account for the changes in resource availability and to adjust the carrying capacity in forest stands. From a range of tested variables, we found monthly maximum temperature and monthly excess water to be the most influential on leaf area index dynamics. With the addition of environmental modifiers and a local carrying capacity parameter, root mean square error was reduced to 0.3802 units LAI (m 2 /m 2 ) from a base model RMSE of 0.4427 units LAI (m 2 /m 2 ). The results indicate that the delay component has a small 41-day effect in the model, which is contrary to our initial hypothesis that stored within-tree carbohydrates can be used for further seasons to build foliage.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Kinane, Stephen M. and Montes, Cristian R. and Zapata, Mauricio and Bullock, Bronson P. and Cook, Rachel L. and Mishra, Deepak R.}, year={2022}, month={Nov} }
 @article{hackman_rose_frank_vilgalys_cook_garcia_2022, title={NPK fertilizer use in loblolly pine plantations: Who are we really feeding?}, volume={520}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85133447940&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2022.120393}, abstractNote={Optimizing loblolly pine (Pinus taeda L.) productivity using fertilizers and various site management practices has been a goal of foresters for decades. Nitrogen (N), phosphorus (P), and potassium (K) are the three most operationally applied fertilizers to loblolly pine silviculture and are of primary importance to their total productivity. Fertilizer recommendations for N, P, and K in loblolly pine are primarily made on abiotic factors such as site and soil characteristics, while the biological factors controlling nutrient uptake are typically overlooked in the production and optimization of these stands. Arguably the most important of these biological factors are the diverse ectomycorrhizal fungal (ECM) communities that colonize the fine roots of almost all loblolly pine trees. The mantle formed by ECM fungi on short-root tips presents a barrier for direct apoplastic uptake of N, P, and K from soil solution by pine roots. In well-colonized roots, the tree is dependent on symplastic fungal transport of N, P, and K foraged from the soil by the extraradical hyphal network. This raises the question: Who are we really feeding if the ECM fungi are the ones assimilating most of the tree's total nutritional requirements? Considering multiple species of ECM fungi can inhabit a single root system, many questions remain regarding the drivers of colonization, why some species are more efficient at taking up and exchanging nutrients with their hosts than others, and why certain fertilizers directly affect the morphology of ECM growth. The purposes of this review are (1) to explore how the most commonly commercially applied macronutrients, N, P, and K, affect the relationship between loblolly pine and ECM communities, and (2) to propose future directions to investigate, preserve, and manipulate these interactions in pine plantations to optimize productivity.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Hackman, Jacob J. and Rose, Benjamin D. and Frank, Hannah E. R. and Vilgalys, Rytas and Cook, Rachel L. and Garcia, Kevin}, year={2022}, month={Sep} }
 @article{shively_cook_maier_garcia_albaugh_campoe_leggett_2022, title={Readily Available Resources Across Sites and Genotypes Result in Greater Growth and Reduced Fine Root Production in Pinus Taeda}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85128591454&partnerID=MN8TOARS}, journal={SSRN}, author={Shively, T.J. and Cook, R. and Maier, C.A. and Garcia, K. and Albaugh, T.J. and Campoe, O. and Leggett, Z.}, year={2022} }
 @article{shively_cook_maier_garcia_albaugh_campoe_leggett_2022, title={Readily available resources across sites and genotypes result in greater aboveground growth and reduced fine root production in Pinus taeda}, volume={521}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85134756753&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2022.120431}, abstractNote={Fine roots serve as the primary interface between trees and the soil, and they are dynamic in their response to environmental conditions.Among many functions, they are principle in gathering nutrients and water, and they constitute a major component of the tree.Their overall contribution to soil carbon flux is not well understood, nor is the effect of site and genotype on their dynamics, and these factors are crucial to understanding nutrient cycles and tree growth under variable conditions.This study evaluated how the fine root dynamics of loblolly pine (Pinus taeda L.) might be different between genotypes and on different sites.Three loblolly pine plantations were established, two in 2009 in North Carolina (NC) and Virginia (VA), and one in 2011 in Brazil (BR).Root biomass was estimated with soil cores across the three sites and between two genotypes in 2020.Seasonal and annual fine root production was measured at the NC and VA sites over the 12th growing season using ingrowth cores.The trees in BR that were two years younger were much larger than those in NC and VA and had more fine root biomass at initial sampling than those in NC, despite similar levels of fertility.Meanwhile, fine root production rates decreased with higher rates of aboveground productivity across all measured plots in NC and VA.These results indicate that (1) standing fine root biomass may be related to environmental conditions that are not easily manipulated, which could inform modeling of carbon cycles, and (2) in these intensively managed plots, sufficient resources were available to allow for increased aboveground growth despite lower rates of fine root production, which supports the employment of these intensive silvicultural practices.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Shively, Timothy J. and Cook, Rachel and Maier, Chris A. and Garcia, Kevin and Albaugh, Timothy J. and Campoe, Otavio and Leggett, Zakiya}, year={2022}, month={Oct} }
 @misc{carter_allen_fox_albaugh_rubilar_campoe_cook_2021, title={A 50-Year Retrospective of the Forest Productivity Cooperative in the Southeastern United States: Regionwide Trials}, volume={119}, ISSN={["1938-3746"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85106551850&partnerID=MN8TOARS}, DOI={10.1093/jofore/fvaa046}, abstractNote={Abstract}, number={1}, journal={JOURNAL OF FORESTRY}, author={Carter, David R. and Allen, H. Lee and Fox, Thomas R. and Albaugh, Timothy J. and Rubilar, Rafael A. and Campoe, Otavio C. and Cook, Rachel L.}, year={2021}, month={Jan}, pages={73–85} }
 @article{albaugh_albaugh_carter_cook_cohrs_rubilar_campoe_2021, title={Duration of response to nitrogen and phosphorus applications in mid-rotation Pinus taeda}, volume={498}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85112486933&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2021.119578}, abstractNote={We quantified the response duration to one-time applications of 112, 224, and 336 kg ha−1 of elemental nitrogen (112 N, 224 N, and 336 N, respectively) combined with 28 or 56 kg ha−1 of elemental phosphorus in mid-rotation Pinus taeda L. stands. Post-application measurements continued for 10 years at 32 sites in the southeastern United States and one site in Argentina, and we fit a Ricker model to data from each treatment in the event that a zero growth response was not observed in our measured data. The response duration was eight (measured), 14 (modeled), and 16 (modeled) years after treatment for the respective 112 N, 224 N, and 336 N treatments. The corresponding growth response per unit of applied nitrogen estimated from fertilization to when the growth response was not different from zero (whether measured or modeled) was 0.20, 0.16, and 0.13 m3 kg−1 for the 112 N, 224 N, and 336 N treatments, respectively. We hypothesized that the mechanism controlling the response duration was related to the amount of fertilizer nitrogen remaining in the foliage over time after treatment; previous studies found that nitrogen application had large impacts on the foliage amount and foliar nitrogen content. Based on retranslocation rate estimates from the literature of 67% of fertilizer nitrogen per year, our results suggest that a good correlation exists between the growth response and the amount of fertilizer nitrogen remaining in the foliage.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Albaugh, Timothy J. and Albaugh, Janine M. and Carter, David R. and Cook, Rachel L. and Cohrs, Chris W. and Rubilar, Rafael A. and Campoe, Otavio C.}, year={2021}, month={Oct} }
 @article{sumnall_trlica_carter_cook_schulte_campoe_rubilar_wynne_thomas_2021, title={Estimating the overstory and understory vertical extents and their leaf area index in intensively managed loblolly pine (Pinus taeda L.) plantations using airborne laser scanning}, volume={254}, ISSN={["1879-0704"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85097899818&partnerID=MN8TOARS}, DOI={10.1016/j.rse.2020.112250}, abstractNote={Data from four discrete-return airborne laser scanning (ALS) acquisitions and three different sensor types across seven experimentally varied loblolly pine (Pinus taeda L.) plantations were used to test published and novel methodologies in quantifying forest structural attributes within stands, including height to live crown (HTLC; i.e. the lowest vertical canopy extent) of the canopy and the contributions to total plot-level leaf area from understory and overstory canopy vegetation. These ALS data were compared to in situ field measurements to develop ALS-based predictive models of these attributes. The correlation between field- and ALS-modeled HTLC data was strong, with an R2 of 0.79 (p < 0.001). We assessed the ability of eight lidar light penetration indices to estimate effective leaf area index (eLAI) in the field. The best predictor of total (sum of understory and overstory) eLAI produced an R2 of 0.88 (p < 0.001). The independent contributions of overstory and understory components could also be accurately predicted by ALS-derived canopy-only eLAI metrics (R2 = 0.71; p < 0.001) and understory-only metrics (R2 = 0.49; p < 0.001). Two new indices, calculated as the sum of return intensity for each foliar layer and correcting for transmission losses, were developed specifically for the vertical strata related to the understory (BLunder) or overstory (BLover). The estimates from BLover were equivalent to the best-performing indices for predicting canopy-only eLAI and the corresponding BLunder was superior to other indices for understory eLAI. The broad spatial and temporal extents of the data, as well as the inclusion of pine plantations with differing stand ages, planting densities, understory control, and thinning treatments, suggest the relationships generated from these methods are robust to site and seasonal variability. The results produced from the analysis of multiple acquisitions implies that the methods presented here are transferable across location, time and sensor design, without implementation-specific calibration, at least for structurally similar loblolly pine plantations.}, journal={REMOTE SENSING OF ENVIRONMENT}, author={Sumnall, Matthew J. and Trlica, Andrew and Carter, David R. and Cook, Rachel L. and Schulte, Morgan L. and Campoe, Otavio C. and Rubilar, Rafael A. and Wynne, Randolph H. and Thomas, Valerie A.}, year={2021}, month={Mar} }
 @article{grover_cook_zapata_urrego_albaugh_zelaya_ozyhar_rubilar_carter_campoe_2021, title={Eucalyptus grandis Response to Calcium Fertilization in Colombia}, volume={67}, ISSN={["1938-3738"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85121035283&partnerID=MN8TOARS}, DOI={10.1093/forsci/fxab042}, abstractNote={Abstract}, number={6}, journal={FOREST SCIENCE}, author={Grover, Zach S. and Cook, Rachel L. and Zapata, Marcela and Urrego, J. Byron and Albaugh, Timothy J. and Zelaya, Ariel and Ozyhar, Tomasz and Rubilar, Rafael and Carter, David R. and Campoe, Otavio C.}, year={2021}, month={Dec}, pages={701–710} }
 @article{brito_rubilar_cook_campoe_carter_mardones_2021, title={Evaluating remote sensing indices as potential productivity and stand quality indicators for Pinus radiata plantations}, volume={49}, ISSN={["1413-9324"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85104990073&partnerID=MN8TOARS}, DOI={10.18671/scifor.v49n129.08}, abstractNote={The objective of the present research was to evaluate the use of several spectral vegetation indices (SVIs), including NDVI, SAVI, SR and RSR, obtained from Landsat 7 images, as potential predictors of forest productivity of radiata pine stands. We aimed to evaluate relationships between the variations in stand volume and SVIs over time and the effect of early weed control on stand growth response. We evaluated a large-scale silviculture experiment located at the Central Valley of Chile, since its establishment until 12 years of age, where weed control showed to be the major silvicultural response. Forest inventory measurements were made annually and local equations were used to estimate stand volume. Significant and highly significant correlation was found among SVI ́s and stand productivity parameters. The best relationship was found between NDVI and stand cumulative volume (R-adj=0.92, p-value < 0.0001, RMSE= 0.03), but SR and RSR were able to better track productivity and the major weed control effect on stand volume growth over time. SVIs’ coefficient of variation estimates were correlated with estimates of stand productivity variability but no significant relationships were established to provide an index of stand quality due to the sensor spatial resolution and plot sizes. SVIs may serve as important tools to monitor forest growth and high-resolution imagery may provide valuable estimates of stand variability for inventory assessment or as a support tool for growth and yield models.}, number={129}, journal={SCIENTIA FORESTALIS}, author={Brito, Vitor Vannozzi and Rubilar, Rafael Alejandro and Cook, Rachel Louise and Campoe, Otavio Camargo and Carter, David Robert and Mardones, Oscar}, year={2021}, month={Mar} }
 @article{trlica_cook_albaugh_parajuli_carter_rubilar_2021, title={Financial Returns for Biomass on Short-Rotation Loblolly Pine Plantations in the Southeastern United States}, volume={67}, ISSN={["1938-3738"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85121028148&partnerID=MN8TOARS}, DOI={10.1093/forsci/fxab033}, abstractNote={Abstract}, number={6}, journal={FOREST SCIENCE}, publisher={Oxford University Press (OUP)}, author={Trlica, Andrew and Cook, Rachel L. and Albaugh, Timothy J. and Parajuli, Rajan and Carter, David R. and Rubilar, Rafael A.}, year={2021}, month={Dec}, pages={670–681} }
 @article{gao_gray_cohrs_cook_albaugh_2021, title={Longer greenup periods associated with greater wood volume growth in managed pine stands}, volume={297}, ISSN={["1873-2240"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85096009084&partnerID=MN8TOARS}, DOI={10.1016/j.agrformet.2020.108237}, abstractNote={Increasing forest productivity is important to meet future demand for forest products, and to improve resilience in the face of climate change. Forest productivity depends on many things, but the timing of leaf development (hereafter: "plant phenology") is especially important. However, our understanding of how plant phenology affects the productivity of managed forests, and how silviculture may in turn affect phenology, has been limited because of the spatial scale mismatch between phenological data and field experimental observations. In this study, we take advantage of a new 30 m satellite land surface phenology dataset and stand growth measurements from long-term experimental pine plantation sites in the southeastern United States to investigate the question: is stand growth related to remotely sensed phenology metrics? Multiple linear regression and random forest models were fitted to quantify the effect of phenology and silvicultural treatments on stand growth. We found that 1) Greater wood volume growth was associated with longer green up periods; 2) Fertilization elevated EVI2 measurement values during the whole growing season, especially in the winter; 3) Competing vegetation could affect remotely sensed observations and complicates interpretation of remotely sensed phenology metrics.}, journal={AGRICULTURAL AND FOREST METEOROLOGY}, publisher={Elsevier BV}, author={Gao, Xiaojie and Gray, Josh and Cohrs, Chris W. and Cook, Rachel and Albaugh, Timothy J.}, year={2021}, month={Feb} }
 @article{hall_stape_bullock_frederick_wright_scolforo_cook_2020, title={A Growth and Yield Model for Eucalyptus benthamii in the Southeastern United States}, volume={66}, ISSN={["1938-3738"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85081127822&partnerID=MN8TOARS}, DOI={10.1093/forsci/fxz061}, abstractNote={Abstract}, number={1}, journal={FOREST SCIENCE}, author={Hall, Kevin B. and Stape, J. L. and Bullock, Bronson P. and Frederick, Doug and Wright, Jeff and Scolforo, Henrique F. and Cook, Rachel}, year={2020}, month={Feb}, pages={25–37} }
 @article{scolforo_montes_cook_allen_albaugh_rubilar_campoe_2020, title={A New Approach for Modeling Volume Response from Mid-Rotation Fertilization ofPinus taedaL. Plantations}, volume={11}, ISSN={["1999-4907"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85087994086&partnerID=MN8TOARS}, DOI={10.3390/f11060646}, abstractNote={Mid-rotation fertilization presents an opportunity to increase the economic return of plantation forests in the southeastern United States (SEUS). For this reason, the Forest Productivity Cooperative established a series of mid-rotation fertilization trials in Pinus taeda L. plantations across the SEUS between 1984 and 1987. These trials identified site-specific responses to nitrogen (N) and phosphorus (P) fertilizers, resulting in increased stand production for 6–10 years after fertilization. There are successful volume response models that allow users to quantify the gain in stand productivity resulting from fertilization. However, all the current models depend on empirical relationships that are not bounded by biological response, meaning that greater fertilizer additions continue to create more volume gains, regardless of physiological limits. To address this shortcoming, we developed a bounded response model that evaluates relative volume response gain to fertilizer addition. Site index and relative spacing are included as model parameters to help provide realistic estimates. The model is useful for evaluating productivity gain in Pinus taeda stands that are fertilized with N and P in mid-rotation.}, number={6}, journal={FORESTS}, author={Scolforo, Henrique F. and Montes, Cristian and Cook, Rachel L. and Allen, Howard Lee and Albaugh, Timothy J. and Rubilar, Rafael and Campoe, Otavio}, year={2020}, month={Jun} }
 @article{carter_albaugh_campoe_grossman_rubilar_sumnall_maier_cook_fox_2020, title={Complementarity increases production in genetic mixture of loblolly pine (Pinus taeda L.) throughout planted range}, volume={11}, ISSN={["2150-8925"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85097304208&partnerID=MN8TOARS}, DOI={10.1002/ecs2.3279}, abstractNote={Abstract}, number={11}, journal={ECOSPHERE}, author={Carter, David R. and Albaugh, Timothy J. and Campoe, Otavio C. and Grossman, Jake J. and Rubilar, Rafael A. and Sumnall, Matthew and Maier, Christopher A. and Cook, Rachel L. and Fox, Thomas R.}, year={2020}, month={Nov} }
 @article{albaugh_maier_campoe_yanez_carbaugh_carter_cook_rubilar_fox_2020, title={Crown architecture, crown leaf area distribution, and individual tree growth efficiency vary across site, genetic entry, and planting density}, volume={34}, ISSN={["1432-2285"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85071645632&partnerID=MN8TOARS}, DOI={10.1007/s00468-019-01898-3}, abstractNote={We examined crown architecture and within crown leaf area distribution effects on Pinus taeda L. growth in North Carolina (NC), Virginia (VA), and Brazil (BR) to better understand why P. taeda can grow much better in Brazil than in the southeastern United States. The NC, VA, and BR sites were planted in 2009, 2009, and 2011, respectively. At all sites, we planted the same two genetic entries at 618, 1236, and 1854 trees ha−1. In 2013, when trees were still open grown, the VA and NC sites had greater branch diameter (24%), branch number (14%), live crown length (44%), foliage mass (82%), and branch mass (91%), than the BR site. However, in 2017, after crown closure and when there was no significant difference in tree size, site did not significantly affect these crown variables. In 2013, site significantly affected absolute leaf area distribution, likely due to differences in live crown length and leaf area, such that there was more foliage at a given level in the crown at the VA and NC sites than at the BR site. In 2017, site was still a significant factor explaining leaf area distribution, although at this point, with crown closure and similar sized trees, there was more foliage at the BR site at a given level in the crown compared to the VA and NC sites. In 2013 and 2017, when including site, genetic entry, stand density, and leaf area distribution parameters as independent variables, site significantly affected individual tree growth efficiency, indicating that something other than leaf area distribution was influencing the site effect. Better BR P. taeda growth is likely due to a combination of factors, including leaf area distribution, crown architecture, and other factors that have been identified as influencing the site effect (heat sum), indicating that future work should include a modeling analysis to examine all known contributing factors.}, number={1}, journal={TREES-STRUCTURE AND FUNCTION}, author={Albaugh, Timothy J. and Maier, Chris A. and Campoe, Otavio C. and Yanez, Marco A. and Carbaugh, Eric D. and Carter, David R. and Cook, Rachel L. and Rubilar, Rafael A. and Fox, Thomas R.}, year={2020}, month={Feb}, pages={73–88} }
 @article{raymond_fox_cook_albaugh_rubilar_2020, title={Losses of fertilizer nitrogen after a winter fertilization in three managed pine plantations of the southeastern United States}, volume={84}, ISSN={["1435-0661"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85081895628&partnerID=MN8TOARS}, DOI={10.1002/saj2.20017}, abstractNote={Abstract}, number={2}, journal={SOIL SCIENCE SOCIETY OF AMERICA JOURNAL}, author={Raymond, Jay E. and Fox, Thomas R. and Cook, Rachel L. and Albaugh, Timothy J. and Rubilar, Rafael}, year={2020}, pages={609–617} }
 @article{srour_ammar_subedi_pimentel_cook_bond_fakhoury_2020, title={Microbial Communities Associated With Long-Term Tillage and Fertility Treatments in a Corn-Soybean Cropping System}, volume={11}, ISSN={["1664-302X"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85087693866&partnerID=MN8TOARS}, DOI={10.3389/fmicb.2020.01363}, abstractNote={Tillage and fertilization are common practices used to enhance soil fertility and increase yield. Changes in soil edaphic properties associated with different tillage and fertility regimes have been widely examined, yet, the microbially mediated pathways and ecological niches involved in enhancing soil fertility are poorly understood. The effects of long-term conventional tillage and no-till in parallel with three fertility treatments (No fertilization, N-only, and NPK) on soil microbial communities were investigated in a long-term field study that was established in the 1970’s. Here, we used high-throughput sequencing of bacterial, fungal and oomycetes markers, followed by community-level functional and ecological assembly to discern principles governing tillage and fertility practices’ influence on associated soil microbiomes. Both tillage and fertilizer significantly altered microbial community structure, but the tillage effect was more prominent than the fertilizer effect. Tillage significantly affected bacteria, fungi, fusaria, and oomycete beta-diversity, whereas fertilizer only affected bacteria and fungi beta-diversity. In our study different tillage and fertilizer regimes favored specific networks of metabolic pathways and distinct ecological guilds. No-till selected for beneficial microbes that translocate nutrients and resources and protect the host against pathogens. Notably, ecological guilds featuring arbuscular mycorrhizae, mycoparasites, and nematophagous fungi were favored in no-till soils, while fungal saprotrophs and plant pathogens dominated in tilled soils. Conventional till and fertilizer management shifted the communities toward fast growing competitors. Copiotrophic bacteria and fusarium species were favored under conventional tillage and in the presence of fertilizers. The analysis of the metagenomes revealed a higher abundance of predicted pathways associated with energy metabolism, translation, metabolism of cofactors and vitamins, glycan biosynthesis and nucleotide metabolism in no-till. Furthermore, no specific pathways were found to be enriched under the investigated fertilization regimes. Understanding how tillage and fertilizer management shift microbial diversity, structure and ecological niches, such as presented here, can assist with designing farming systems that can maintain high crop yield, while reducing soil erosion and nutrient losses.}, journal={FRONTIERS IN MICROBIOLOGY}, author={Srour, Ali Y. and Ammar, Hala A. and Subedi, Arjun and Pimentel, Mirian and Cook, Rachel L. and Bond, Jason and Fakhoury, Ahmad M.}, year={2020}, month={Jun} }
 @article{schulte_cook_albaugh_allen_rubilar_pezzutti_lucia caldato_campoe_carter_2020, title={Mid-rotation response of Pinus taeda to early silvicultural treatments in subtropical Argentina}, volume={473}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85086739488&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2020.118317}, abstractNote={Pinus taeda plantations in subtropical areas of South America are extremely productive and commonly established on well-drained red clay sites. In the past, land with more poorly-drained soil was avoided due to concern over the factors limiting site productivity. Establishment of intensively managed plantations on poorly-drained soils usually includes soil preparation by subsoiling and/or bedding, weed control, and fertilization. However, forest managers lack information about the efficacy of early silvicultural practices to ameliorate environmental limitations and if these intensive practices generate long-term improvements in productivity in this area. Consequently, we established studies in northeastern Argentina on two sites differing by drainage class and soil texture as a full factorial design with site preparation (S; disking and disking + subsoiling (red clay) or bedding (wet loam)), fertilization (F; none or 78 kg ha−1 elemental phosphorus at planting), and weed control (W; none or two-year banded). Seven years after planting, the red clay and wet loam sites were equally productive, with maximum treatment means of 218 m3 ha−1 and 264 m3 ha−1 respectively. At the red clay site, only weed control significantly increased volume. At the wet loam site, both weed control and site preparation significantly increased volume, mainly due to increased survival. The combination of weed control and bedding yielded a non-additive volume response as indicated by a significant W*S interaction. Our results do not support the common practice of subsoiling on red clay soils. In addition, fertilization with P alone appears counterproductive or unneeded at both sites.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Schulte, Morgan L. and Cook, Rachel L. and Albaugh, Timothy J. and Allen, H. Lee and Rubilar, Rafael A. and Pezzutti, Raul and Lucia Caldato, Silvana and Campoe, Otavio and Carter, David R.}, year={2020}, month={Oct} }
 @article{dhakal_singh_cook_sievers_2020, title={Modeling Hairy Vetch and Cereal Rye Cover Crop Decomposition and Nitrogen Release}, volume={10}, ISSN={["2073-4395"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85085510241&partnerID=MN8TOARS}, DOI={10.3390/agronomy10050701}, abstractNote={Empirical models could help us to understand the process of plant residue decomposition and nutrient release into the soil. The objective of this study was to determine an appropriate model to describe the decomposition of hairy vetch (Vicia villosa Roth) and cereal rye (Secale cereale L.) cover crop (CC) residue and nitrogen (N) release. Data pertaining to above and belowground CC residue mass loss and N release for up to 2633 cumulative decomposition degree days (112 d) after litterbag installation were obtained from two cropping system experiments, a 1-yr study conducted in 2015 and a 2-yr study during 2017 to 2018 in the humid subtropical environment of southern IL, USA. Six exponential and two hyperbolic models were fit to percent mass and N remaining data to find the one with minimum Akaike information criterion (AIC) and residual sum of squares. Modified three-parameter single exponential and two- or three-parameter hyperbolic models best met the assumed criteria of selection for above and belowground CC residue, respectively. Fitting a double exponential model to combined data for percent mass and N remaining identified two mass and N pools, a fast and a slow pool with different rate constants. A five-parameter double exponential with an asymptote met the preset criteria and passed all tests for normally distributed population, constant variance, and independence of residuals at α = 0.05 when fit to combined data of hairy vetch shoot mass and N remaining. However, a two-parameter hyperbolic and three-parameter asymptotic hyperbolic model provided the best fit to a combined data of cereal rye shoot mass and N remaining, respectively. Both hyperbolic decay models showed a good fit for belowground mass decomposition and N release for both CCs. Cereal rye had a poorer fit than hairy vetch for mass and N remaining of both above and belowground mass. The best-selected decay models can be used to estimate the decomposition and N release rates of hairy vetch and cereal rye above and belowground residue in a similar environment.}, number={5}, journal={AGRONOMY-BASEL}, author={Dhakal, Madhav and Singh, Gurbir and Cook, Rachel L. and Sievers, Taylor}, year={2020}, month={May} }
 @article{cohrs_cook_gray_albaugh_2020, title={Sentinel-2 Leaf Area Index Estimation for Pine Plantations in the Southeastern United States}, volume={12}, ISSN={2072-4292}, url={http://dx.doi.org/10.3390/rs12091406}, DOI={10.3390/rs12091406}, abstractNote={Leaf area index (LAI) is an important biophysical indicator of forest health that is linearly related to productivity, serving as a key criterion for potential nutrient management. A single equation was produced to model surface reflectance values captured from the Sentinel-2 Multispectral Instrument (MSI) with a robust dataset of field observations of loblolly pine (Pinus taeda L.) LAI collected with a LAI-2200C plant canopy analyzer. Support vector machine (SVM)-supervised classification was used to improve the model fit by removing plots saturated with aberrant radiometric signatures that would not be captured in the association between Sentinel-2 and LAI-2200C. The resulting equation, LAI = 0.310SR − 0.098 (where SR = the simple ratio between near-infrared (NIR) and red bands), displayed good performance (     R 2      = 0.81, RMSE = 0.36) at estimating the LAI for loblolly pine within the analyzed region at a 10 m spatial resolution. Our model incorporated a high number of validation plots (n = 292) spanning from southern Virginia to northern Florida across a range of soil textures (sandy to clayey), drainage classes (well drained to very poorly drained), and site characteristics common to pine forest plantations in the southeastern United States. The training dataset included plot-level treatment metrics—silviculture intensity, genetics, and density—on which sensitivity analysis was performed to inform model fit behavior. Plot density, particularly when there were ≤618 trees per hectare, was shown to impact model performance, causing LAI estimates to be overpredicted (to a maximum of      X i      + 0.16). Silviculture intensity (competition control and fertilization rates) and genetics did not markedly impact the relationship between SR and LAI. Results indicate that Sentinel-2’s improved spatial resolution and temporal revisit interval provide new opportunities for managers to detect within-stand variance and improve accuracy for LAI estimation over current industry standard models.}, number={9}, journal={Remote Sensing}, publisher={MDPI AG}, author={Cohrs, Chris W. and Cook, Rachel L. and Gray, Josh M. and Albaugh, Timothy J.}, year={2020}, month={Apr}, pages={1406} }
 @article{singh_thilakarathne_williard_schoonover_cook_gage_mcelroy_2020, title={Tillage and legume non-legume cover cropping effects on corn–soybean production}, volume={112}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85085084230&partnerID=MN8TOARS}, DOI={10.1002/agj2.20221}, abstractNote={Abstract}, number={4}, journal={Agronomy Journal}, author={Singh, G. and Thilakarathne, A.D.G.M. and Williard, K.W.J. and Schoonover, J.E. and Cook, R.L. and Gage, K.L. and McElroy, R.}, year={2020}, pages={2636–2648} }
 @article{albaugh_fox_cook_raymond_rubilar_campoe_2019, title={Forest Fertilizer Applications in the Southeastern United States from 1969 to 2016}, volume={65}, ISSN={["1938-3738"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85065724434&partnerID=MN8TOARS}, DOI={10.1093/forsci/fxy058}, abstractNote={This study presents forest fertilization and carbon sequestered from fertilization in the southeastern United States in the context of newly available silviculture management information. Maximum annual fertilized forest area in the southeastern United States occurred in 1999 when 1.58 million acres were fertilized. Since then, the fertilized area has generally declined, and in 2016, 589,000 acres were fertilized. This decline is likely related to new research and changes in economic conditions. Recent research has determined that lower, more frequent nutrient doses gave the same biological response as larger, less frequent doses; improved our understanding and use of urease inhibitors; and quantified the upper limit to pine productivity in the southeast United States. All of these factors combined with economic concerns including the continued low number of housing starts, a large inventory of stands with trees that are already sawtimber size, and low sawtimber prices influence forest managers’ decisions about fertilization. However, fertilization increases carbon sequestration in forests, and carbon markets that recognize this contribution to sequestration are developing and may provide additional income to forest managers and, ultimately, increase the area fertilized.}, number={3}, journal={FOREST SCIENCE}, author={Albaugh, Timothy J. and Fox, Thomas R. and Cook, Rachel L. and Raymond, Jay E. and Rubilar, Rafael A. and Campoe, Otavio C.}, year={2019}, month={Jun}, pages={355–362} }
 @article{bernardina batista_scolforo_mello_guedes_nunes santos terra_scalon_gomide_vitor scolforo_cook_2019, title={Spatial association of fruit yield of Bertholletia excelsa Bonpl. trees in eastern Amazon}, volume={441}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85063289242&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2019.03.043}, abstractNote={Brazil nut (Bertholletia excelsa) is one of the most important non-timber forest product (NTFP) species in the world. Better management and conservation practices will only be possible with an in-depth knowledge of tree species ecology. This study aimed to assess the spatial association of fruit yield of Bertholletia excelsa (B. excelsa) trees in two forest types (old growth terra firme forest and Amazon-cerrado transitional forest) in the Brazilian Amazon. Fruit yield was measured in both forest types during 2010. At each forest type, fruit yield was divided into different yield classes (number of fruits) for subsequent spatial modeling. The bivariate Ripley’s K-function was applied to quantify the spatial association of fruit yield of B. excelsa trees over different fruit yield classes. The results revealed that the forest type influences the spatial association of B. excelsa fruit yield. The old growth terra firme forest presented random spatial association for fruit yield, which implies that fruit yield of B. excelsa trees in this forest type is not limited by tree location and site resources. On the other hand, the Amazon-cerrado transitional forest presented significant negative spatial association for fruit yield across different yield classes, which means that under some conditions fruit yield of a given tree influences the fruit yield of the neighboring tree in this forest type. Site resources in the Amazon-cerrado transitional forest is limited and naturally favors inter- and intra-specific competition. Finally, the results imply the need for adoption of different management and conservation strategies for B. excelsa in different forest types in the Brazilian Amazon.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Bernardina Batista, Anderson Pedro and Scolforo, Henrique Ferraco and Mello, Jose Marcio and Guedes, Marcelino Carneiro and Nunes Santos Terra, Marcela Castro and Scalon, Joao Domingos and Gomide, Lucas Rezende and Vitor Scolforo, Paula Gomides and Cook, Rachel L.}, year={2019}, month={Jun}, pages={99–105} }
 @article{maier_burley_cook_ghezehei_hazel_nichols_2019, title={Tree Water Use, Water Use Efficiency, and Carbon Isotope Discrimination in Relation to Growth Potential in Populus deltoides and Hybrids under Field Conditions}, volume={10}, ISSN={1999-4907}, url={http://dx.doi.org/10.3390/f10110993}, DOI={10.3390/f10110993}, abstractNote={We explored the relationship between tree growth, water use, and related hydraulic traits in Populus deltoides Bartr. ex Marsh.and hybrid clones, to examine potential trade-offs between growth and water use efficiency. Nine genotypes, six P. deltoides and three hybrid clones, that represented genotypes with high (Group H), intermediate (Group I), and low (Group L) growth performance were selected for study, based on year-two standing stem biomass in a replicated field trial. In year four, tree growth, transpiration (Et), canopy stomatal conductance (Gs), whole-tree hydraulic conductance (Gp), and carbon isotope discrimination (Δ13C) were measured. Tree sap flux was measured continuously using thermal dissipation probes. We hypothesized that Group H genotypes would have increased growth efficiency (GE), increased water use efficiency of production (WUEp, woody biomass growth/Et), lower Δ13C, and greater Gp than slower growing genotypes. Tree GE increased with relative growth rate (RGR), and mean GE in Group H was significantly greater than L, but not I. Tree WUEp ranged between 1.7 and 3.9 kg biomass m3 H2O−1, which increased with RGR. At similar levels of Et, WUEp was significantly greater in Group H (2.45 ± 0.20 kg m−3), compared to I (2.03 ± 0.18 kg m−3) or L (1.72 ± 0.23 kg m−3). Leaf and wood Δ13C scaled positively with stem biomass growth but was not correlated with WUEp. However, at a similar biomass increment, clones in Group H and I had significantly lower leaf Δ13C than Group L. Similarly, Group H clones had a significantly lower wood Δ13C than Group L, supporting our hypothesis of increased WUE in larger trees. Tree physiological and hydraulic traits partially explain differences in WUEp and Δ13C, and suggest that clone selection and management activities that increase tree biomass production will likely increase tree and stand WUE. However, more research is needed to discern the underlying hydraulic mechanisms responsible for the higher WUE exhibited by large trees and distinct clones.}, number={11}, journal={Forests}, publisher={MDPI AG}, author={Maier and Burley and Cook and Ghezehei and Hazel and Nichols}, year={2019}, month={Nov}, pages={993} }
 @article{albaugh_fox_maier_campoe_rubilar_cook_raymond_alvares_stape_2018, title={A common garden experiment examining light use efficiency and heat sum to explain growth differences in native and exotic Pinus taeda}, volume={425}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85047245176&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2018.05.033}, abstractNote={Previous work indicates that Pinus taeda L. grows faster and has a higher carrying capacity when grown outside its native range. We were interested in examining the hypotheses that growth, light use efficiency (volume growth and absorbed photosynthetically active radiation relationship, LUE) and volume growth per unit heat sum is the same for native and exotic plantations. To test these hypotheses, we installed a common garden experiment where the same six genetic entries of P. taeda (four clonal varieties, one open pollinated family and one control mass pollinated family) were planted at three densities (618, 1235, and 1853 stems ha−1) with three or four replications at three sites (Virginia (VA), and North Carolina (NC) in the United States and Paraná State in Brazil (BR)). The VA and BR sites were outside the native range of P. taeda. After five years of growth, the BR site had larger trees and stand scale basal area and volume were increasing faster than the other sites. Site did not affect LUE but density and genetic entry did. The sites were at different latitudes but the average photosynthetically active radiation at the top of the canopy was similar for the years when all sites were operational, likely because the BR site receives more rain annually and the cloudiness associated with the rain may have reduced available light. We estimated an hourly heat sum where the daytime temperature was between 5 and 38 °C, hours where vapor pressure deficit exceeded 1.5 kPa and days following nights where nighttime temperatures were less than 0 °C were excluded. Site was significant for the cumulative volume and heat sum relationship, for a given level of cumulative degree hours the sites ranked BR > VA > NC in cumulative volume. The different growth per unit of degree hours for each site indicated that something other than the heat sum was causing the observed difference in growth. Other factors including respiration and extreme climatic conditions may contribute to growth differences per unit degree hour and including these differences in the analysis would require a more detailed modeling effort to examine. The sites used in this study are ideally suited to continue testing additional hypotheses to explain the different growth between native and exotic P. taeda plantations because they have the same genotypes at all sites and consequently eliminate differences in genetics as a potential explanation for observed growth differences.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Albaugh, Timothy J. and Fox, Thomas R. and Maier, Chris A. and Campoe, Otavio C. and Rubilar, Rafael A. and Cook, Rachel L. and Raymond, Jay E. and Alvares, Clayton A. and Stape, Jose L.}, year={2018}, month={Oct}, pages={35–44} }
 @article{sievers_cook_2018, title={Aboveground and Root Decomposition of Cereal Rye and Hairy Vetch Cover Crops}, volume={82}, ISSN={["1435-0661"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85042135277&partnerID=MN8TOARS}, DOI={10.2136/sssaj2017.05.0139}, abstractNote={
Core Ideas
Hairy vetch decomposed faster than cereal rye.
Hairy vetch released N within two weeks of termination.
Biomass belowground decomposed more quickly than aboveground.
Cover crop N release occurred earlier than maximum crop uptake due to late planting.
Synchronizing cover crop decomposition and nutrient release with cash crop uptake can provide benefits to agroecosystems but can be difficult to implement. The objectives of this study were to quantify the aboveground and belowground decomposition and nutrient release of two cover crops, hairy vetch (Vicia villosa Roth) and cereal rye (Secale cereale L.), after termination with herbicides through a 16‐wk period during the cash crop growing season using litterbags and intact root cores. Plant Root Simulator probes monitored mineral N in the soil. Hairy vetch aboveground (k = 0.4505) and root (k = 0.6821) biomass decomposed at a faster rate than aboveground (k = 0.1368) and root (k = 0.1866) biomass of cereal rye. Hairy vetch had higher initial N content in aboveground (41.9 g kg–1) and root (16.5 g kg–1) biomass than cereal rye (11.5 and 8.3 g kg–1, respectively). Hairy vetch had a lower C to N ratio than cereal rye in both aboveground (9.52 vs. 34.72) and root biomass (17.31 vs. 40.31) contributing to decomposition differences. Hairy vetch rapidly decomposed after cover crop termination in the spring, therefore growers should consider delaying termination of this cover crop until close to cash crop planting to decrease the risk of N loss. Cereal rye residues decompose much slower and may also immobilize N because of its high C to N ratio. A better understanding of how aboveground and belowground cover crop characteristics influence decomposition will help to optimize cover crop nutrient release with cash crop uptake.}, number={1}, journal={SOIL SCIENCE SOCIETY OF AMERICA JOURNAL}, author={Sievers, Taylor and Cook, Rachel L.}, year={2018}, pages={147–155} }
 @article{rubilar_allen_fox_cook_albaugh_campoe_2018, title={Advances in Silviculture of Intensively Managed Plantations}, volume={4}, ISSN={["2198-6436"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85050372148&partnerID=MN8TOARS}, DOI={10.1007/s40725-018-0072-9}, number={1}, journal={CURRENT FORESTRY REPORTS}, author={Rubilar, Rafael A. and Allen, H. Lee and Fox, Thomas R. and Cook, Rachel L. and Albaugh, Timothy J. and Campoe, Otavio C.}, year={2018}, month={Mar}, pages={23–34} }
 @article{walia_krausz_cook_2018, title={Does Tillage or Fertilizer Provide Resilience to Extreme Weather in Southern Illinois?}, volume={110}, ISSN={["1435-0645"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85052694457&partnerID=MN8TOARS}, DOI={10.2134/agronj2017.11.0641}, abstractNote={Core Ideas
Dry weather causes maximum reduction in yields of corn and soybean.
Precipitation during silking increases yields of corn.
In cold years, no‐till yielded 7.5% higher than alternate tillage and chisel tillage.
Fertilizer placement had significant effects on corn yields during normal and dry weather years only.
}, number={5}, journal={AGRONOMY JOURNAL}, author={Walia, Maninder K. and Krausz, Ronald F. and Cook, Rachel L.}, year={2018}, pages={2091–2097} }
 @article{sunderlage_cook_2018, title={Soil Property and Fertilizer Additive Effects on Ammonia Volatilization from Urea}, volume={82}, ISSN={["1435-0661"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85042070447&partnerID=MN8TOARS}, DOI={10.2136/sssaj2017.05.0151}, abstractNote={
Core Ideas
Total exchange capacity was the best soil predictor of volatilization from urea.
Urease activity and pH were not effective predictors of volatilization from urea.
NBPT effectively reduces ammonia volatilization compared with nonamended urea.
NBPT efficacy was reduced in more acidic soils.
Calcium salt of maleic‐itaconic copolymer did not reduce ammonia volatilization.
Urea efficiency can be substantially reduced through nitrogen loss as ammonia (NH3–N), which is controlled by soil properties and environmental conditions. A laboratory incubation measured the effects of a range of soil properties on ammonia volatilization over 7 d from 168 kg N ha–1 as surface‐applied urea and the efficacy of two fertilizer additives: urea plus a commercial formulation of N‐(n‐butyl) thiophosphoric triamide (NBPT) + N‐(n‐propyl) thiophosphoric triamide (NPPT) (urea + NBPT/NPPT) and urea plus a commercial formulation of calcium salt of maleic‐itaconic copolymer (MIP) from 79 soils across the United States. Total exchange capacity (TEC), 0.01 mol L–1 CaCl2 pH (pH), soil organic matter (SOM), hydroxide buffering capacity (OHBC), clay content, and urease activity were measured as predictors. Generalized regression models identified that TEC, clay content, OHBC, and SOM accounted for most variation in NH3–N losses in urea (R2 = 0.69) and urea + MIP (R2 = 0.67). Total exchange capacity was the strongest predictor of volatilization; greater TEC resulted in lower NH3–N losses. pH and TEC accounted for the most variation in NH3–N loss among soils fertilized with urea + NBPT/NPPT (R2 = 0.58). Volatilization increased with lower pH in urea + NBPT/NPPT, indicating that NBPT efficacy decreases in acidic soils, potentially due to faster chemical degradation. The addition of NBPT/NPPT to urea significantly reduced volatilization from 24.5 to 6.3% of applied N (P < 0.0001), whereas urea + MIP did not reduce volatilization (P = 0.9707).}, number={1}, journal={SOIL SCIENCE SOCIETY OF AMERICA JOURNAL}, author={Sunderlage, Brent and Cook, Rachel L.}, year={2018}, pages={253–259} }
 @article{albaugh_rubilar_maier_acuna_cook_2017, title={'Biomass and nutrient mass of Acacia dealbata and Eucalyptus globulus bioenergy plantations}, volume={97}, ISSN={["1873-2909"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85008967232&partnerID=MN8TOARS}, DOI={10.1016/j.biombioe.2016.12.025}, abstractNote={We quantified biomass and nutrient accumulation of Acacia dealbata Link and Eucalyptus globulus Labill. planted at stem densities of 5000 and 15000 ha−1 in a bioenergy plantation in Chile. We tested the hypotheses that species and stocking will not affect biomass or nutrient accumulation. Species and stocking did not affect biomass accumulation after five years; however, species and stocking did influence nutrient mass. A. dealbata had higher nitrogen mass than E. globulus for total (397 kg ha−1 more, i.e., 126% higher), foliage (188 kg ha−1, 218%), branch (55 kg ha−1, 95%), stem (120 kg ha−1, 86%), and root (34 kg ha−1, 109%) components, likely because A. dealbata fixes nitrogen. A. dealbata had lower calcium mass than E. globulus for branch (111 kg ha−1, 60%) and stem (69 kg ha−1, 39%) components. Root nitrogen and phosphorus masses and foliage, branch and root boron masses were significantly lower with a stocking density of 5000 ha−1. Low stocking produced the same amount of total biomass as high stocking for both species and would be less expensive to plant. A. dealbata had higher nitrogen mass and likely increased soil nitrogen. E. globulus had high calcium mass in the stem and branches; off-site losses could be mitigated with stem-only harvests and debarking of stems in the field. Given the rainfall patterns and water availability constraints in Chile, additional criteria including water use efficiency would be required to determine the best species for bioenergy plantations in Chile.}, journal={BIOMASS & BIOENERGY}, author={Albaugh, Timothy J. and Rubilar, Rafael A. and Maier, Chris A. and Acuna, Eduardo A. and Cook, Rachel L.}, year={2017}, month={Feb}, pages={162–171} }
 @article{maier_albaugh_cook_hall_mcinnis_johnsen_johnson_rubilar_vose_2017, title={Comparative water use in short-rotation Eucalyptus benthamii and Pinus taeda trees in the Southern United States}, volume={397}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85018772782&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2017.04.038}, abstractNote={Short rotation Eucalyptus plantations offer great potential for increasing wood-fiber production in the southern United States. Eucalyptus plantations can be highly productive (>35 m3 ha−1 year−1), but they may use more water than intensively managed pine (primarily Pinus taeda L.) plantations. This has raised concern about how expansion of Eucalyptus plantations will affect water resources. We compared tree water use, stem growth, and WUE (kg wood per m3 water transpired) in adjacent nine-year-old Eucalyptus benthamii and P. taeda plantations with similar stand density and leaf area. Sap flux (Fd, g cm−2 s−1) was measured continuously over one year using thermal dissipation probes. Stem biomass, stem growth, tree water use (Et, L day−1), canopy transpiration per unit leaf area (El, mmol m−2 s−1), and canopy stomatal conductance (Gs, mmol m−2 s−1) were quantified. Eucalyptus had higher daily Fd (196.6 g cm−2 day−1) and mean daily Et (24.6 L day−1) than pine (105.8 g cm−2 day−1, 15.2 L day−1). Eucalyptus exhibited a seasonally bimodal pattern in daily Et that did not occur in pine. Monthly Et was 23–51% higher in Eucalyptus and differences between species were greatest in the spring and fall. Annual Et was 32% higher in Eucalyptus (9.13 m3 H2O year−1) than pine (5.79 m3 H2O year−1). Annual stem biomass increment was greater in Eucalyptus (Eucalyptus: 22.9; pine: 11.8 kg tree−1 year−1), and Eucalyptus had greater WUE (Eucalyptus: 2.86; pine 1.72 kg biomass m−3 H2O year−1). Pine exhibited a lower seasonal minimum and higher seasonal maximum leaf area index (LAI). At low LAI, there was no significant difference between species in El or Gs; however, at maximum LAI, pine El and Gs were 46 and 43%, respectively of rates observed in Eucalyptus. The species differed in Gs response to vapor pressure deficit (D). At a similar reference Gs (Gs,ref at D = 1 kPa), pine exhibited greater stomatal sensitivity to D. These results suggest that (1) Eucalyptus trees had higher sap flux and total water use than pine, (2) Eucalyptus had greater stem growth and WUE, and (3) species differences in water use were driven primarily by differences in El and Gs.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Maier, Chris A. and Albaugh, Timothy J. and Cook, Rachel I. and Hall, Kevin and McInnis, Daniel and Johnsen, Kurt H. and Johnson, John and Rubilar, Rafael A. and Vose, James M.}, year={2017}, month={Aug}, pages={126–138} }
 @article{trlica_walia_krausz_secchi_cook_2017, title={Continuous Corn and Corn-Soybean Profits over a 45-Year Tillage and Fertilizer Experiment}, volume={109}, ISSN={["1435-0645"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85010375436&partnerID=MN8TOARS}, DOI={10.2134/agronj2016.06.0377}, abstractNote={Core Ideas
Cumulative profit (1970–2014) in no‐till was similar to other tillage types with NPK.
Relative profits were more sensitive to changes in machinery than herbicide cost.
Return on fertilizer ranged from 56 to 251% for P and K and 69 to 434% for N.
}, number={1}, journal={AGRONOMY JOURNAL}, author={Trlica, Andrew and Walia, Maninder K. and Krausz, Ron and Secchi, Silvia and Cook, Rachel L.}, year={2017}, pages={218–226} }
 @article{walia_baer_krausz_cook_2017, title={Deep soil carbon after 44 years of tillage and fertilizer management in southern Illinois compared to forest and restored prairie soils}, volume={72}, ISSN={["1941-3300"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85033214332&partnerID=MN8TOARS}, DOI={10.2489/jswc.72.4.405}, abstractNote={No-till (NT) management can reduce soil erosion and increase soil carbon (C) in agricultural systems, but there is less certainty regarding deeper soil and how long-term tillage and fertilization practices compare to other land-use systems. The objective of this study was to quantify tillage and fertilizer management effects after 44 years (20 years in continuous corn [Zea mays L.] and 24 years in corn–soybean [Glycine max L.] rotation) on bulk density and soil C concentrations and stocks to a 1 m (3.3 ft) depth in a somewhat poorly drained Bethalto silt loam near Belleville, Illinois, and compare to nearby forest and restored prairie soils. Four tillage (moldboard plow, chisel tillage [ChT], alternate tillage, and NT) and five fertilizer (no fertilization control, nitrogen [N]-only, N + N-phosphorus-potassium [NPK] starter, NPK + NPKstarter, and NPK broadcast) treatments showed bulk density was lower in NT than moldboard plow treatments in 0 to 15 (0 to 6 in) and 25 to 50 cm (10 to 20 in) depths. Complete NPK treatments generally resulted in higher C stocks than N-only and control treatments from 0 to 25 cm (0 to 10 in), but no differences were detected from 25 to 100 cm (10 to 39 in) or 0 to 100 cm (0 to 39 in) due to fertilizer. No-till management increased C stocks compared to tillage treatments for 0 to 15 cm (0 to 6 in) and was greater than the ChT treatment for 0 to 100 cm (0 to 39 in). No-till/NPK maintained greater cumulative soil C stocks to 1 m than either undisturbed forest soils or restored prairie soils. Additionally, NT/NPK had the maximum soil C increase over time of 0.36 Mg C ha−1 y−1 (0.16 tn C ac−1 yr−1) for the top 15 cm (6 in) over 44 years.}, number={4}, journal={JOURNAL OF SOIL AND WATER CONSERVATION}, author={Walia, M. K. and Baer, S. G. and Krausz, R. and Cook, R. L.}, year={2017}, pages={405–415} }
 @article{eagle_christianson_cook_harmel_miguez_qian_ruiz diaz_2017, title={Meta-analysis constrained by data: Recommendations to improve relevance of nutrient management research}, volume={109}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85034043845&partnerID=MN8TOARS}, DOI={10.2134/agronj2017.04.0215}, abstractNote={Core Ideas
Data and reporting deficiencies reduce the effectiveness of agri‐environmental meta‐analysis.
Standardization and consistency across studies will enhance data synthesis and meta‐analysis.
Reporting standard sets of data and meta‐data will extend the value of agricultural field research.
}, number={6}, journal={Agronomy Journal}, author={Eagle, A.J. and Christianson, L.E. and Cook, R.L. and Harmel, R.D. and Miguez, F.E. and Qian, S.S. and Ruiz Diaz, D.A.}, year={2017}, pages={2441–2449} }
 @article{albaugh_fox_rubilar_cook_amateis_burkhart_2017, title={Post-thinning density and fertilization affect Pinus taeda stand and individual tree growth}, volume={396}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85018352159&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2017.04.030}, abstractNote={We installed a thinning and fertilization study at five sites in mid-rotation Pinus taeda L. stands in the southeastern United States to examine treatment effects on diameter growth, basal area production, and volume increment. The treatments were four levels of post-thinning stand density (247, 494, 741 and 1235 stems ha−1) and two levels of fertilization (none and 224 and 28 kg ha−1 of elemental nitrogen and phosphorus, respectively), applied in four replications at each site using either a randomized complete block (3 sites) or a split plot (2 sites) design. Six years after treatment, thinning significantly increased diameter and diameter increment as the residual density level decreased and increased stand basal area, stand basal area increment, stand volume and stand volume increment as residual density level increased at all sites. Fertilizer significantly increased diameter and stand basal area increments at two sites and stand volume increment at one site; these sites had low initial leaf area index, a metric commonly used to assess the potential for response to fertilization. Diameter increment increased as initial diameter class increased. Larger trees grew faster than smaller trees at all sites and for all treatments. Diameter growth decreased as initial stand basal area increased, and fertilization significantly increased diameter growth for a given level of initial stand basal area at sites where fertilization affected diameter growth. Stand volume increment increased as diameter increment increased for crop trees (largest 247 stems ha−1), whereas stand volume increment decreased as diameter increment increased for all trees. The stand-scale ‘cost’ for greater individual-tree diameter growth was a reduction in stand volume increment in the 247 stems ha−1 treatment; this reduction was 13 m3 ha−1 yr−1 across all sites compared with the 1235 stems ha−1 treatment, whereas the individual tree diameter growth ‘benefit’ was 0.9 cm yr−1 when comparing these same treatments. Trade-offs were quantified between individual tree size and stand growth across the thinning and fertilization levels imposed in this study, which will be useful in empirical and process-based modeling efforts for predicting thinning and fertilization responses of P. taeda.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Albaugh, Timothy J. and Fox, Thomas R. and Rubilar, Rafael A. and Cook, Rachel L. and Amateis, Ralph L. and Burkhart, Harold E.}, year={2017}, month={Jul}, pages={207–216} }
 @article{cook_binkley_stape_2016, title={Eucalyptus plantation effects on soil carbon after 20 years and three rotations in Brazil}, volume={359}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84943605697&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2015.09.035}, abstractNote={How will shifting land use from row crops and pasture to intensively managed forests alter soil carbon storage? Demand and profitability has led to a dramatic increase in Eucalyptus production with a total planted area over 20 million hectares worldwide. The impacts of these short-rotation (6- to 8-year harvest cycle) Eucalyptus plantations on soil carbon appear to be variable, and the available case studies are typically too short term to support generalization. Spatial heterogeneity of soils across landscapes requires repeated sampling for reliable documentation of soil carbon changes over multiple rotations. We characterized soil carbon stocks and change over two decades in 306 operational Eucalyptus plantations across a 1200-km gradient. Across all sites, soil C (0–30 cm depth) in 2010 averaged 29 Mg ha−1 (± 0.70 Mg ha−1), tending to increase with increasing soil clay content, precipitation, and mean annual temperature. Average soil C from the original sampling to 2010 (ranging from 18 to 26 years or approximately 3 to 4 rotations) showed a slight decrease (−0.22 ± 0.05 Mg ha−1 yr−1, P < 0.0001). Tropical sites in Region 1 (Bahia state) showed no net change (−0.11 Mg ha−1 yr−1, P = 0.1874, whereas tropical and subtropical sites in Region 2 (Espirito Santo state) lost soil carbon stocks (−0.87 Mg ha−1 yr−1, P < 0.0001), and subtropical sites in Region 3 (São Paulo state) also remained the same (0.06 Mg ha−1 yr−1, P = 0.3969). Soil carbon change tended to increase with precipitation during the dry season, and had weaker associations with soil order and mean annual temperature.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Cook, Rachel L. and Binkley, Dan and Stape, Jose Luiz}, year={2016}, month={Jan}, pages={92–98} }
 @article{cook_trlica_2016, title={Tillage and fertilizer effects on crop yield and soil properties over 45 years in Southern Illinois}, volume={108}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84953727800&partnerID=MN8TOARS}, DOI={10.2134/agronj2015.0397}, abstractNote={Reducing soil disturbance may limit erosion, but many still consider tillage essential for seedbed preparation, particularly on poorly drained soils. Our objective was to quantify tillage and fertilizer management effects after 45 yr {21 in continuous corn [Zea mays L.] [CC] and 24 in corn–soybean [Glycine max (L.) Merr.] [CS] rotation} on a somewhat poorly drained silt loam near Belleville, IL. Four tillage (moldboard plow [MP], chisel tillage [ChT], alternate tillage [AT], and no‐till [NT]) and five fertilizer (no fertilization, N‐only, N+NPK starter, NPK+NPK starter, and NPK broadcast) treatments were evaluated. With N, P, and K fertilizer, yields were similar for tilled and NT treatments, averaging 8.73 Mg ha−1 for CC and 11.93 Mg ha−1 and 3.70 Mg ha−1 for rotated corn and soybean. Below recommended soil‐test values resulted in NT yielding less than tilled treatments even though soil test P, K, and pH were similar. No‐till with N, P, and K increased soil organic matter (OM) to 27.6 g kg−1 (20.5 g kg−1 in all other treatments), with the greatest increase from 0‐ to 5‐cm. No‐till treatments showed stratification of P and K, but it had no effect on yield. No excessive pH stratification was observed. Overall, fertilizer management predominantly influenced crop yield and with complete NPK management non‐tilled yields were similar to tilled, even on flat, somewhat‐poorly drained soils. No‐till with NPK management therefore may allow farmers to maintain high yields while reducing soil and nutrient losses.}, number={1}, journal={Agronomy Journal}, author={Cook, R.L. and Trlica, A.}, year={2016}, pages={415–426} }
 @article{campoe_iannelli_stape_cook_mendes_vivian_2014, title={Atlantic forest tree species responses to silvicultural practices in a degraded pasture restoration plantation: From leaf physiology to survival and initial growth}, volume={313}, ISSN={0378-1127}, url={http://dx.doi.org/10.1016/J.FORECO.2013.11.016}, DOI={10.1016/J.FORECO.2013.11.016}, abstractNote={Deforestation has led to ecosystem degradation in many tropical regions. Re-establishment of native tree species on degraded land presents challenges due to environmental stressors such as water and nutrient limitations, particularly from weed competition. Ecophysiological studies can help assess responses of native tree species to silvicultural practices and improve our understanding of processes that influence their establishment and growth. Silvicultural treatments borrowed from commercial tree plantations such as greater nutrient applications and complete weed control can improve best silvicultural practices in forest restoration. Two contrasting silvicultural treatments, “traditional” based on common management practices for reforestation of native trees and “intensive” based on commercial plantation silviculture, were evaluated based on tree mortality, biomass, photosynthesis, chlorophyll content, soluble proteins, and nutritional status of 20 native Brazilian species, 2.5 years after planting. Intensive silviculture increased tree survival by 20%, showed higher aboveground biomass from 13% to 7-fold and increased photosynthesis of ∼20% from 15.8 μmol m−2 s−1 to 18.7 μmol m−2 s−1, compared to traditional silviculture. Total soluble proteins were 14% higher with 6.7 μg cm−2 in intensive silviculture compared to 5.9 μg cm−2 under traditional silviculture. Eighty percent of trees showed greater N content, with a 13% higher average than under traditional silviculture (2.60 g m−2 versus 2.92 g m−2). Average values of chlorophyll A, B, and total were ∼8% higher under intensive silviculture, but not significantly different between treatments. Overall, intensive silviculture provided a positive impact on the restoration plantation. During the initial years of plantation establishment, intensive silviculture methods were effective in leading to significant increases in growth and survival.}, journal={Forest Ecology and Management}, publisher={Elsevier BV}, author={Campoe, Otávio C. and Iannelli, Cláudia and Stape, José Luiz and Cook, Rachel L. and Mendes, João Carlos T. and Vivian, Rafael}, year={2014}, month={Feb}, pages={233–242} }
 @article{nichols_cook_landmeyer_atkinson_malone_shaw_woods_2014, title={Phytoremediation of a Petroleum-Hydrocarbon Contaminated Shallow Aquifer in Elizabeth City, North Carolina, USA}, volume={24}, ISSN={1051-5658}, url={http://dx.doi.org/10.1002/REM.21382}, DOI={10.1002/REM.21382}, abstractNote={A former bulk fuel terminal in North Carolina is a groundwater phytoremediation demonstration site where 3,250 hybrid poplars, willows, and pine trees were planted from 2006 to 2008 over approximately 579,000 L of residual gasoline, diesel, and jet fuel. Since 2011, the groundwater altitude is lower in the area with trees than outside the planted area. Soil‐gas analyses showed a 95 percent mass loss for total petroleum hydrocarbons (TPH) and a 99 percent mass loss for benzene, toluene, ethylbenzene, and xylenes (BTEX). BTEX and methyl tert‐butyl ether concentrations have decreased in groundwater. Interpolations of free‐phase, fuel product gauging data show reduced thicknesses across the site and pooling of fuel product where poplar biomass is greatest. Isolated clusters of tree mortalities have persisted in areas with high TPH and BTEX mass. Toxicity assays showed impaired water use for willows and poplars exposed to the site's fuel product, but Populus survival was higher than the willows or pines on‐site, even in a noncontaminated control area. All four Populus clones survived well at the site. © 2014 Wiley Periodicals, Inc.*}, number={2}, journal={Remediation Journal}, publisher={Wiley}, author={Nichols, Elizabeth Guthrie and Cook, Rachel L. and Landmeyer, James E. and Atkinson, Brad and Malone, Donald R. and Shaw, George and Woods, Leilani}, year={2014}, month={Mar}, pages={29–46} }
 @article{cook_stape_binkley_2014, title={Soil carbon dynamics following reforestation of tropical pastures}, volume={78}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84893255184&partnerID=MN8TOARS}, DOI={10.2136/sssaj2012.0439}, abstractNote={Soil carbon changes following reforestation of tropical pasture soils have been variable and the mechanisms poorly understood. This limits predictive capabilities and therefore management decisions. Photosynthetic pathways of C4 grasses and C3 trees create unique stable carbon isotopic signatures that can be used to determine soil carbon dynamics. In this study, mineral soils were sampled to 45 cm from paired land cover types consisting of an unmanaged forest and pasture, pastures paired with broadleaf plantations, and broadleaf paired with conifer plantations. Soil δ13C values were determined from pastures (SOC4) and forests (SOC3), allowing the calculation of turnover time of SOC4 following reforestation. Reforested pasture soils became dominated by SOC3 in 10 years at 0 to 15 cm and in 8 yr at 15 to 30 cm, but remained dominated by SOC3 from original forest cover from 30 to 45 cm. From 0 to 15 cm, the rate of SOC3 accumulation (0.21 Mg C ha-1 yr-1) matched the rate of SOC4 disappearance (-0.21 Mg C ha-1 yr-1). Soil carbon decreased slightly in the 15- to 30-cm (-0.17 Mg C ha-1 yr-1) and 30- to 45-cm (-0.08 Mg C ha-1 yr-1) soil layers from a loss of SOC4 and no gain of SOC3. Overall, reforestation led to relatively small net losses of mineral soil C (-0.20 Mg C ha-1 yr-1, 0–45 cm). Turnover time for SOC4 increased with depth from 30 to 73 yr. The results from this analysis contribute to a better understanding of soil carbon dynamics following reforestation of tropical pastures.}, number={1}, journal={Soil Science Society of America Journal}, author={Cook, R.L. and Stape, J.L. and Binkley, D.}, year={2014}, pages={290–296} }
 @article{cook_binkley_mendes_stape_2014, title={Soil carbon stocks and forest biomass following conversion of pasture to broadleaf and conifer plantations in southeastern Brazil}, volume={324}, ISSN={["1872-7042"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84898814028&partnerID=MN8TOARS}, DOI={10.1016/j.foreco.2014.03.019}, abstractNote={Increased soil carbon sequestration can potentially mitigate CO2 emission and can indicate sustainable forest management. This study aims to determine the relative influence of commercial plantation tree species on soil carbon following establishment on former tropical pastures. Soil carbon (organic horizon plus mineral soil from 0 to 45 cm) and stemwood productivity were quantified from 6 to 34 year-old conifer and broadleaf plantations in a sandy Oxisol (Typic Hapludox) in southeastern Brazil. Study plots consisted of ten pastures paired with broadleaf plantations and ten additional broadleaf plantations paired with conifer plantations. Pastures primarily consisted of Brachiaria decumbens Stapf., while broadleaf plantations were primarily Eucalyptus, but also included one plot each of three other broadleaf species. Conifer stands were made up of Pinus species. Average stemwood productivity (± standard error) was 9.7 (±1.0) Mg C ha−1 yr−1 for broadleaf and 5.7 (±0.5) Mg C ha−1 yr−1 for conifer plantations, but did not correlate to soil C. The soil C in the paired Pasture–Broadleaf plots averaged 36.0 ± 1.7 Mg C ha−1 in pastures and 36.8 ± 1.9 Mg C ha−1 in broadleaf plantations. The Broadleaf–Conifer plots averaged 38.3 ± 1.9 Mg C ha−1 for broadleaf plantations and 36.0 ± 1.6 Mg C ha−1 for conifers. Our results show little difference in soil C across vegetation types, providing evidence that conifer and broadleaf plantations overall maintain similar levels of soil carbon to pasture land-use up to 34 years following land conversion. Soil C differences between Pasture–Broadleaf pairs indicated a small decline in soil C accretion early after plantation establishment, followed by recovery to slightly higher accretion rates.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Cook, Rachel L. and Binkley, Dan and Mendes, Joao Carlos T. and Stape, Jose Luiz}, year={2014}, month={Jul}, pages={37–45} }
 @article{cook_hesterberg_2013, title={Comparison of Trees and Grasses for Rhizoremediation of Petroleum Hydrocarbons}, volume={15}, ISSN={["1549-7879"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84874598499&partnerID=MN8TOARS}, DOI={10.1080/15226514.2012.760518}, abstractNote={Rhizoremediation of petroleum contaminants is a phytoremediation process that depends on interactions among plants, microbes, and soils. Trees and grasses are commonly used for phytoremediation, with trees typically being chosen for remediation of BTEX while grasses are more commonly used for remediation of PAHs and total petroleum hydrocarbons. The objective of this review was to compare the effectiveness of trees and grasses for rhizoremediation of hydrocarbons and address the advantages of each vegetation type. Grasses were more heavily represented in the literature and therefore demonstrated a wider range of effectiveness. However, the greater biomass and depth of tree roots may have greater potential for promoting environmental conditions that can improve rhizoremediation, such as increased metabolizable organic carbon, oxygen, and water. Overall, we found little difference between grasses and trees with respect to average reduction of hydrocarbons for studies that compared planted treatments with a control. Additional detailed investigations into plant attributes that most influence hydrocarbon degradation rates should provide data needed to determine the potential for rhizoremediation with trees or grasses for a given site and identify which plant characteristics are most important.}, number={9}, journal={INTERNATIONAL JOURNAL OF PHYTOREMEDIATION}, author={Cook, Rachel L. and Hesterberg, Dean}, year={2013}, month={Oct}, pages={844–860} }
 @article{cook_landmeyer_atkinson_messier_nichols_2010, title={Field Note: Successful Establishment of a Phytoremediation System at a Petroleum Hydrocarbon Contaminated Shallow Aquifer: Trends, Trials, and Tribulations}, volume={12}, ISSN={["1549-7879"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77956951220&partnerID=MN8TOARS}, DOI={10.1080/15226510903390395}, abstractNote={We report the establishment of a mixed hybrid poplar (Populus spp.) and willow (Salix spp.) phytoremediation system at a fuel-contaminated site. Several approaches were used to balance competing goals of cost-effectiveness yet successful tree establishment without artificial irrigation or trenching. Bare root and unrooted cuttings were installed using either: (1) 1.2 m deep holes excavated with an 8 cm diameter auger using a direct-push rig and backfilled with the excavated, in situ soil; (2) 1.2 m deep holes created with a 23 cm diameter auger attached to a Bobcat rig and backfilled with clean topsoil from offsite; and (3) shallow holes between 15–30 cm deep that were created with a 1.3 cm diameter rod and no backfill. Tree mortality from initial plantings indicated contaminated zones not quantified in prior site investigations and remedial actions. Aquifer heterogeneity, underground utilities, and prior remediation infrastructure hampered the ability of the site to support a traditional experimental design. Total stem length and mortality were measured for all planted trees and were incorporated into a geographic information system. Planting early in the growing season, augering a larger diameter hole, and backfilling with clean, uncontaminated topsoil was cost effective and allowed for greater tree cutting growth and survival.}, number={7}, journal={INTERNATIONAL JOURNAL OF PHYTOREMEDIATION}, author={Cook, Rachel L. and Landmeyer, James E. and Atkinson, Brad and Messier, Jean-Pierre and Nichols, Elizabeth Guthrie}, year={2010}, pages={716–732} }