@article{ile_typhina_brannum_parajuli_bardon_2023, title={Toward the Adoption of New Farming Systems among Farmers: A Case study of Short Rotation Woody Crops in North Carolina}, volume={61}, ISSN={["1077-5315"]}, DOI={10.34068/joe.61.01.09}, abstractNote={This study explores the human dimensions of the broad-based adoption of Short Rotation Woody Crops (SRWCs) among farmers in North Carolina. We used an actor diagramming and tracing approach to explore factors influencing farmers’ adoption of SRWCs. Results suggest four factors strongly influence the adoption process: 1) market availability, 2) education awareness, 3) funding, and 4) social networking. Based on these results, we recommend that Extension professionals use the following education modules to prompt the adoption of SRWCs practices and potentially adopt other new farming practices: 1) ecological sustainability, 2) financial considerations, 3) harvesting, and 4) community building.}, number={1}, journal={JOURNAL OF EXTENSION}, author={Ile, Omoyemeh J. and Typhina, Eli and Brannum, Katie and Parajuli, Rajan and Bardon, Robert E.}, year={2023} }
 @article{carvalho_aguilos_ile_howard_king_heitman_2023, title={Water use of short-rotation coppice American sycamore (Platanus occidentalis L.) for bioenergy during establishment on marginal land in the North Carolina Piedmont}, volume={276}, ISSN={0378-3774}, url={http://dx.doi.org/10.1016/j.agwat.2022.108071}, DOI={10.1016/j.agwat.2022.108071}, abstractNote={American sycamore (Platanus occidentalis L.) is a hardwood species that can be integrated into short-rotation coppice (SRC) production systems for bioenergy in the southeastern USA. Due to high growth rates and low input requirements, sycamore is regarded as a promising second-generation bioenergy woody crop suitable for degraded or marginal lands. However, little is known about sycamore water use for the conditions of North Carolina (NC), especially during the establishment year when trees are most sensitive to soil water deficits. We evaluated energy fluxes and actual crop evapotranspiration (ETc act) rates of sycamore SRC during the establishment year on marginal land in the Piedmont physiographic region of NC. Our overall goal was to better understand the factors controlling the evaporative demand of sycamore and its sensitivity to drought stress during establishment. Total ETc act was 482 mm, which was 95% of the total rainfall at the site. ETc act rates increased with precipitation and with tree development, reaching a maximum of 5.7 mm d−1. Although severe water stress was not observed during the study period, a moderate drought occurred from mid-August to mid-September, during which a 13-day drying cycle caused ETc act rates to decrease by 30%. The sycamore SRC transitioned from an “energy-limited” to a “water-limited” ETc act regime when water content in the upper 5 cm of soil was about 0.10 m3 m−3, indicating that the sycamore field relied on water available within the upper soil layers. Measurements suggested that trees may not yet have developed a root system sufficient to sustain transpiration during dry spells and that water use of the sycamore field was highly coupled to precipitation during the establishment year.}, journal={Agricultural Water Management}, publisher={Elsevier BV}, author={Carvalho, Henrique D.R. and Aguilos, Maricar M. and Ile, Omoyemeh J. and Howard, Adam M. and King, John S. and Heitman, Joshua L.}, year={2023}, month={Feb}, pages={108071} }
 @article{morkoc_aguilos_noormets_minick_ile_dickey_hardesty_kerrigan_heitman_king_2022, title={Environmental and Plant-Derived Controls on the Seasonality and Partitioning of Soil Respiration in an American Sycamore (Platanus occidentalis) Bioenergy Plantation Grown at Different Planting Densities}, volume={13}, ISSN={1999-4907}, url={http://dx.doi.org/10.3390/f13081286}, DOI={10.3390/f13081286}, abstractNote={Bioenergy is one of the most considered alternatives to fossil fuels. Short-rotation woody crops (SRWCs) as bioenergy sources are capable of alleviating energy constraints and sequestering atmospheric CO2. However, studies investigating soil carbon (C) dynamics at SWRC plantations are scarce. We studied American sycamore (Platanus occidentalis) as a model tree species for SRWC at different planting densities ((1) 0.5 × 2.0 m (10,000 trees·ha−1 or tph), (2) 1.0 × 2.0 m (5000 tph), and (3) 2.0 × 2.0 m (2500 tph)) to examine seasonal variation in total soil respiration (Rtotal), partitioned into heterotrophic (Rh) and autotrophic (Ra) respiration, and we evaluated climatic and biological controls on soil respiration. Rtotal and Rh exhibited larger seasonal variation than Ra (p < 0.05). During the nongrowing seasons, the average Rtotal was 0.60 ± 0.21 g·C·m−2·day−1 in winter and 1.41 ± 0.73 g·C·m−2·day−1 in fall. During the growing season, Rtotal was 2–7 times higher in spring (3.49 ± 1.44 g·C·m−2·day−1) and summer (4.01 ± 1.17 g·C·m−2·day−1) than winter. Average Rtotal was 2.30 ± 0.63 g·C·m−2·day−1 in 2500 tph, 2.43 ± 0.64 g·C·m−2·day−1 in 5000 tph, and 2.41 ± 0.75 g·C·m−2·day−1 in 10,000 tph treatments. Average Rh was 1.72 ± 0.40 g·C·m−2·day−1 in 2500 tph, 1.57 ± 0.39 g·C·m−2·day−1 in 5000 tph, and 1.93 ± 0.64 g·C·m−2·day−1 in 10,000 tph, whereas Ra had the lowest rates, with 0.59 ± 0.53 g·C·m−2·day−1 in 2500 tph, 0.86 ± 0.51 g·C·m−2·d−1 in 5000 tph, and 0.48 ± 0.34 g·C·m−2·day−1 in 10,000 tph treatments. Rh had a greater contribution to Rtotal (63%–80%) compared to Ra (20%–37%). Soil temperature was highly correlated to Rtotal (R2 = 0.92) and Rh (R2 = 0.77), while the correlation to Ra was weak (R2 = 0.21). Rtotal, Rh, and Ra significantly declined with soil water content extremes (e.g., <20% or >50%). Total root biomass in winter (469 ± 127 g·C·m−2) was smaller than in summer (616 ± 161 g·C·m−2), and the relationship of total root biomass to Rtotal, Rh, and Ra was only significant during the growing seasons (R2 = 0.12 to 0.50). The litterfall in 5000 tph (121 ± 16 g DW·m−2) did not differ (p > 0.05) from the 2500 tph (108 ± 16 g DW·m−2) or 10,000 tph (132 ± 16 g DW·m−2) treatments. In no circumstances were Rtotal, Rh, and Ra significantly correlated with litterfall amount across planting densities and seasons (p > 0.05). Overall, our results show that Rtotal in American sycamore SRWC is dominated by the heterotrophic component (Rh), is strongly correlated to soil environmental conditions, and can be minimized by planting at a certain tree density (5000 tph).}, number={8}, journal={Forests}, publisher={MDPI AG}, author={Morkoc, Suna and Aguilos, Maricar and Noormets, Asko and Minick, Kevan J. and Ile, Omoyemeh and Dickey, David A. and Hardesty, Deanna and Kerrigan, Maccoy and Heitman, Joshua and King, John}, year={2022}, month={Aug}, pages={1286} }
 @article{ile_mccormick_skrabacz_bhattacharya_aguilos_carvalho_idassi_baker_heitman_king_2022, title={Integrating Short Rotation Woody Crops into Conventional Agricultural Practices in the Southeastern United States: A Review}, volume={12}, ISSN={2073-445X}, url={http://dx.doi.org/10.3390/land12010010}, DOI={10.3390/land12010010}, abstractNote={One of the United Nations Sustainable Development Goal’s (SDGs) aims is to enhance access to clean energy. In addition, other SDGs are directly related to the restoration of degraded soils to improve on-farm productivity and land management. Integrating Short Rotation Woody Crops (SRWC) for bioenergy into conventional agriculture provides opportunities for sustainable domestic energy production, rural economic development/diversification, and restoration of soil health and biodiversity. Extensive research efforts have been carried out on the development of SRWC for bioenergy, biofuels, and bioproducts. Recently, broader objectives that include multiple ecosystem services, such as carbon sequestration, and land mine reclamation are being explored. Yet, limited research is available on the benefits of establishing SRWC on degraded agricultural lands in the southeastern U.S. thereby contributing to environmental goals. This paper presents a literature review to (1) synthesize the patterns and trends in SWRC bioenergy production; (2) highlight the benefits of integrating short rotation woody crops into row crop agriculture; and (3) identify emerging technologies for efficiently managing the integrated system, while identifying research gaps. Our findings show that integrating SRWC into agricultural systems can potentially improve the climate of agricultural landscapes and enhance regional and national carbon stocks in terrestrial systems.}, number={1}, journal={Land}, publisher={MDPI AG}, author={Ile, Omoyemeh J. and McCormick, Hanna and Skrabacz, Sheila and Bhattacharya, Shamik and Aguilos, Maricar and Carvalho, Henrique D. R. and Idassi, Joshua and Baker, Justin and Heitman, Joshua L. and King, John S.}, year={2022}, month={Dec}, pages={10} }
 @article{aguilos_brown_minick_fischer_ile_hardesty_kerrigan_noormets_king_2021, title={Millennial-Scale Carbon Storage in Natural Pine Forests of the North Carolina Lower Coastal Plain: Effects of Artificial Drainage in a Time of Rapid Sea Level Rise}, volume={10}, ISSN={2073-445X}, url={http://dx.doi.org/10.3390/land10121294}, DOI={10.3390/land10121294}, abstractNote={Coastal forested wetlands provide important ecosystem services along the southeastern region of the United States, but are threatened by anthropogenic and natural disturbances. Here, we examined the species composition, mortality, aboveground biomass, and carbon content of vegetation and soils in natural pine forests of the lower coastal plain in eastern North Carolina, USA. We compared a forest clearly in decline (termed “ghost forest”) adjacent to a roadside canal that had been installed as drainage for a road next to an adjacent forest subject to “natural” hydrology, unaltered by human modification (termed “healthy forest”). We also assessed how soil organic carbon (SOC) accumulation changed over time using 14C radiocarbon dating of wood sampled at different depths within the peat profile. Our results showed that the ghost forest had a higher tree density at 687 trees ha−1, and was dominated by swamp bays (Persea palustric), compared to the healthy forest, which had 265 trees ha−1 dominated by pond pine (Pinus serotina Michx). Overstory tree mortality of the ghost forest was nearly ten times greater than the healthy forest (p < 0.05), which actually contributed to higher total aboveground biomass (55.9 ± 12.6 Mg C ha−1 vs. 27.9 ± 8.7 Mg ha−1 in healthy forest), as the dead standing tree biomass (snags) added to that of an encroaching woody shrub layer during ecosystem transition. Therefore, the total aboveground C content of the ghost forest, 33.98 ± 14.8 Mg C ha−1, was higher than the healthy forest, 24.7 ± 5.2 Mg C ha−1 (p < 0.05). The total SOC stock down to a 2.3 m depth in the ghost forest was 824.1 ± 46.2 Mg C ha−1, while that of the healthy forest was 749.0 ± 170.5 Mg C ha−1 (p > 0.05). Carbon dating of organic sediments indicated that, as the sample age approaches modern times (surface layer year 2015), the organic soil accumulation rate (1.11 to 1.13 mm year−1) is unable to keep pace with the estimated rate of recent sea level rise (2.1 to 2.4 mm year−1), suggesting a causative relationship with the ecosystem transition occurring at the site. Increasing hydrologic stress over recent decades appears to have been a major driver of ecosystem transition, that is, ghost forest formation and woody shrub encroachment, as indicated by the far higher overstory tree mortality adjacent to the drainage ditch, which allows the inland propagation of hydrologic/salinity forcing due to SLR and extreme storms. Our study documents C accumulation in a coastal wetland over the past two millennia, which is now threatened due to the recent increase in the rate of SLR exceeding the natural peat accumulation rate, causing an ecosystem transition with unknown consequences for the stored C; however, much of it will eventually be returned to the atmosphere. More studies are needed to determine the causes and consequences of coastal ecosystem transition to inform the modeling of future coastal wetland responses to environmental change and the estimation of regional terrestrial C stocks and flux.}, number={12}, journal={Land}, publisher={MDPI AG}, author={Aguilos, Maricar and Brown, Charlton and Minick, Kevan and Fischer, Milan and Ile, Omoyemeh J. and Hardesty, Deanna and Kerrigan, Maccoy and Noormets, Asko and King, John}, year={2021}, month={Nov}, pages={1294} }
 @article{ile_aguilos_morkoc_minick_domec_king_2021, title={Productivity of low-input short-rotation coppice American sycamore ( Platanus occidentalis L.) grown at different planting densities as a bioenergy feedstock over two rotation cycles}, volume={146}, ISSN={["1873-2909"]}, url={https://doi.org/10.1016/j.biombioe.2021.105983}, DOI={10.1016/j.biombioe.2021.105983}, abstractNote={Short rotation coppice culture of woody crop species (SRWCs) has long been considered a sustainable method of producing biomass for bioenergy that does not compete with current food production practices. In this study, we grew American sycamore (Platanus occidentalis L.) for nine years corresponding to two rotation cycles (first rotation (FR) = 2010–2014, second rotation (SR) = 2015–2019). This was done at varying tree planting densities (1250, 2500, 5000, and 10,000 trees per hectare (tph)) on a degraded agricultural landscape under low-input (e.g. no fertilizer and low herbicide application) culture, in the Piedmont physiographic region of eastern North Carolina. Tree productivity was proportional to planting density, with the highest cumulative aboveground wood biomass in the 10,000 tph treatment, at 23.2 ± 0.9 Mg ha−1 and 39.1 ± 2.4 Mg ha−1 in the first and second rotations, respectively. These results demonstrate increasing productivity under a low-input SRWC management regime over the first two rotations. Biomass partitioning was strongly affected by planting density during FR, allocating less biomass to stems relative to other plant parts at low planting density (44–59% from 1250 to 10,000 tph, respectively). This effect disappeared during SR, however, with biomass partitioning to stems ranging from 74 to 79% across planting densities. Taken together, our results suggest that American sycamore has the potential to be effectively managed as a bioenergy feedstock with low input culture on marginal agriculture lands.}, journal={BIOMASS & BIOENERGY}, author={Ile, Omoyemeh J. and Aguilos, Maricar and Morkoc, Suna and Minick, Kevan and Domec, Jean-Christophe and King, John S.}, year={2021}, month={Mar} }
 @article{ile_aguilos_morkoc_heitman_king_2021, title={Root Biomass Distribution and Soil Physical Properties of Short-Rotation Coppice American Sycamore (Platanus occidentalis L.) Grown at Different Planting Densities}, volume={12}, ISSN={1999-4907}, url={http://dx.doi.org/10.3390/f12121806}, DOI={10.3390/f12121806}, abstractNote={Short rotation woody crops (SRWCs) provide sustainable, renewable biomass energy and offer potential ecosystem services, including increased carbon storage, reduced greenhouse gas emissions, and improved soil health. Establishing SRWCs on degraded lands has potential to enhance soil properties through root and organic matter turnover. A better understanding of SRWC planting density and its associated root turnover impacts on soil–air–water relations can improve management. In this study, we investigate the effects of planting density for a low-input American sycamore SRWC (no fertilization/irrigation) on soil physical properties for a degraded agricultural site in the North Carolina piedmont. The objectives were (1) to estimate the distributions of coarse and fine root biomass in three planting densities (10,000, 5000, and 2500 trees per hectare (tph)) and (2) to assess the effects of planting density on soil hydraulic properties and pore size distribution. Our results show that planting at 10,000 tph produced significantly higher amounts of fine root biomass than at lower planting densities (p < 0.01). In the 25,000 tph plots, there was significantly higher amounts of coarse root biomass than for higher planting densities (p < 0.05). The 10,000 tph plots had lower plant available water capacity but larger drainable porosity and saturated hydraulic conductivity compared with lower planting densities (<0.05). The 10,000 tph plots total porosity was more dominated by larger pore size fractions compared with the 5000 and 2500 tph. Generally, our findings show similar patterns of soil hydraulic properties and pore size distributions for lower planting densities. The results from 10,000 tph indicate a higher air-filled pore space at field capacity and more rapid drainage compared with lower planting densities. Both characteristics observed in the 10,000 tph are favorable for aeration and oxygen uptake, which are especially important at wet sites. Overall, the results suggest that improved soil health can be achieved from the establishment of American sycamore SRCs on marginal lands, thereby providing a green pathway to achieving environmental sustainability with woody renewable energy.}, number={12}, journal={Forests}, publisher={MDPI AG}, author={Ile, Omoyemeh Jennifer and Aguilos, Maricar and Morkoc, Suna and Heitman, Joshua and King, John S.}, year={2021}, month={Dec}, pages={1806} }