@article{reberg-horton_mueller_mellage_creamer_brownie_bell_burton_2011, title={Influence of field margin type on weed species richness and abundance in conventional crop fields}, volume={26}, ISSN={["1742-1705"]}, DOI={10.1017/s1742170510000451}, abstractNote={AbstractNatural vegetation occurring on farms in field margins, fallow fields, ditch systems and neighboring forests, provides increased biodiversity, structural diversity, habitat for wildlife and beneficial insects, and can act as a protective buffer against agrochemical drift. Nevertheless, farmers frequently view these areas as non-productive and as potential sources of weeds, insect pests and diseases. Weed species richness and abundance were examined in crop fields in 2002–2003 at the Center for Environmental Farming Systems near Goldsboro, NC to determine if crop field weed infestation was associated with field margin management (managed versus unmanaged). Weed species abundance and richness were measured over two growing seasons on four occasions in crop fields along permanent transects that extended from the field edge toward the center of the field. The presence/absence of data for all plant species in the field margin was also recorded. For both margin types, managed and unmanaged, more weeds were found near the field edge than in the center of the field. Weed species richness was slightly higher in cropland bordering managed margins than in cropland along unmanaged margins. Several significant interactions led to an examination of nine dominant weed species in each field margin type and their distribution in crop fields. When all sampling dates were pooled, only 42 (40%) of 105 species identified in the field margins were observed in the crop field. Managed margins had lower species richness than unmanaged field margins—less than half the mean number of species (15 versus 6 species, respectively). Contingency table analysis did not reveal any association between plant species occurring in the margin and those found in the crop field. Furthermore, margin type and weed presence in the field margin were not effective predictors of weed occurrence in the crop field as determined by logistic regression.}, number={2}, journal={RENEWABLE AGRICULTURE AND FOOD SYSTEMS}, publisher={Cambridge University Press (CUP)}, author={Reberg-Horton, S. C. and Mueller, J. P. and Mellage, S. J. and Creamer, N. G. and Brownie, C. and Bell, M. and Burton, M. G.}, year={2011}, month={Jun}, pages={127–136} }
 @article{nathan b. o'berry_faircloth_jones_herbert_abaye_mckemie_brownie_2009, title={Differential Responses of Cotton Cultivars when Applying Mepiquat Pentaborate}, volume={101}, ISSN={["0002-1962"]}, DOI={10.2134/agronj2007.0333}, abstractNote={Plant growth regulators are routinely used in cotton (Gossypium hirsutum L.) production to reduce plant height and hasten maturity. The objective of this research was to determine the response of several cotton cultivars to mepiquat pentaborate (MPB) application in environments accumulating different levels of heat units. Four MPB application regimes were imposed on three cultivars in Virginia and South Carolina in 2005 and 2006. Total MPB season rates of 0.0, 54.9, 85.3, or 121.9 g ai ha−1 applied at the five‐leaf stage, pin‐head square, match‐head square, and early bloom were used. The cultivars were: Deltapine (DP) 444 BG/RR, an “early‐maturing” cultivar; Fibermax (FM) 960 BR, a “medium‐maturing” cultivar; and DP 555 BG/RR, a “late‐maturing” cultivar. In South Carolina in 2006, FM 960 BR July plant height was reduced by 25% with MPB application compared to only 12 and 13% for DP 444 BG/RR and DP 555 BG/RR, respectively, although actual plant height reductions were not different among cultivars. Mepiquat pentaborate applications decreased plant height at harvest by 8 to 34%, height‐to‐node ratio by 10 to 32%, enhanced maturity as measured by nodes above white flower for all cultivars, and decreased lint yield by 3.7 to 8.5% compared to untreated cotton. Higher seasonal totals and earlier initiation of MPB application resulted in the greatest decrease in lint yield.}, number={1}, journal={AGRONOMY JOURNAL}, author={Nathan B. O'Berry and Faircloth, Joel C. and Jones, Michael A. and Herbert, David A., Jr. and Abaye, Azenegashe O. and McKemie, Thomas E. and Brownie, Cavell}, year={2009}, pages={25–31} }
 @article{rothenberger_burkholder_brownie_2009, title={Long-Term Effects of Changing Land Use Practices on Surface Water Quality in a Coastal River and Lagoonal Estuary}, volume={44}, ISSN={["1432-1009"]}, DOI={10.1007/s00267-009-9330-8}, abstractNote={The watershed of the Neuse River, a major tributary of the largest lagoonal estuary on the U.S. mainland, has sustained rapid growth of human and swine populations. This study integrated a decade of available land cover and water quality data to examine relationships between land use changes and surface water quality. Geographic Information Systems (GIS) analysis was used to characterize 26 subbasins throughout the watershed for changes in land use during 1992-2001, considering urban, agricultural (cropland, animal as pasture, and densities of confined animal feed operations [CAFOs]), forested, grassland, and wetland categories and numbers of wastewater treatment plants (WWTPs). GIS was also used together with longitudinal regression analysis to identify specific land use characteristics that influenced surface water quality. Total phosphorus concentrations were significantly higher during summer in subbasins with high densities of WWTPs and CAFOs. Nitrate was significantly higher during winter in subbasins with high numbers of WWTPs, and organic nitrogen was higher in subbasins with higher agricultural coverage, especially with high coverage of pastures fertilized with animal manure. Ammonium concentrations were elevated after high precipitation. Overall, wastewater discharges in the upper, increasingly urbanized Neuse basin and intensive swine agriculture in the lower basin have been the highest contributors of nitrogen and phosphorus to receiving surface waters. Although nonpoint sources have been emphasized in the eutrophication of rivers and estuaries such as the Neuse, point sources continue to be major nutrient contributors in watersheds sustaining increasing human population growth. The described correlation and regression analyses represent a rapid, reliable method to relate land use patterns to water quality, and they can be adapted to watersheds in any region.}, number={3}, journal={ENVIRONMENTAL MANAGEMENT}, author={Rothenberger, Meghan B. and Burkholder, JoAnn M. and Brownie, Cavell}, year={2009}, month={Sep}, pages={505–523} }
 @article{yoshizaki_pollock_brownie_webster_2009, title={Modeling misidentification errors in capture-recapture studies using photographic identification of evolving marks}, volume={90}, ISSN={["1939-9170"]}, DOI={10.1890/08-0304.1}, abstractNote={Misidentification of animals is potentially important when naturally existing features (natural tags) are used to identify individual animals in a capture–recapture study. Photographic identification (photoID) typically uses photographic images of animals' naturally existing features as tags (photographic tags) and is subject to two main causes of identification errors: those related to quality of photographs (non‐evolving natural tags) and those related to changes in natural marks (evolving natural tags). The conventional methods for analysis of capture–recapture data do not account for identification errors, and to do so requires a detailed understanding of the misidentification mechanism. Focusing on the situation where errors are due to evolving natural tags, we propose a misidentification mechanism and outline a framework for modeling the effect of misidentification in closed population studies. We introduce methods for estimating population size based on this model. Using a simulation study, we show that conventional estimators can seriously overestimate population size when errors due to misidentification are ignored, and that, in comparison, our new estimators have better properties except in cases with low capture probabilities (<0.2) or low misidentification rates (<2.5%).}, number={1}, journal={ECOLOGY}, author={Yoshizaki, Jun and Pollock, Kenneth H. and Brownie, Cavell and Webster, Raymond A.}, year={2009}, month={Jan}, pages={3–9} }
 @article{finney_creamer_schultheis_wagger_brownie_2009, title={Sorghum sudangrass as a summer cover and hay crop for organic fall cabbage production}, volume={24}, ISSN={["1742-1713"]}, DOI={10.1017/S174217050999007X}, abstractNote={AbstractNo-tillage (NT) organic vegetable production presents several economic opportunities for growers in the southeastern United States while promoting natural resource conservation. This study was conducted to determine if removal of sorghum sudangrass (SS) cover crop biomass as hay, frequency at which the cover crop is mowed, and tillage affect weed suppression and head weight of transplanted organic cabbage. Sorghum sudangrass [Sorghum bicolor(L.) Moench×Sorgum sudanense(Piper) Staph.] was planted in May 2004 at Reidsville and Goldsboro, NC, preceding the planting of organic ‘Bravo’ cabbage (Brassica oleraceaL. Capitata group) in August and September 2004, respectively. SS management systems included: low-frequency mowing with hay removed following the first mowing operation (LFM-H), low-frequency mowing with hay not removed (LFM), high-frequency mowing with hay not removed (HFM) and a no cover crop control. Two tillage treatments were applied within each management system: conventional tillage (CT) and NT. Under NT conditions, SS mulch generated by LFM offered broadleaf weed control in cabbage similar to that achieved under CT, regardless of whether cover crop biomass was removed as hay. Mowing with higher frequency reduced SS cover crop biomass by 18–33% and reduced weed suppression in NT cabbage. Mowing frequency did not influence the quantity of SS that re-grew in the cabbage crop. SS re-growth contributed to lower head weight in NT compared to CT cabbage in Goldsboro, and crop failure of NT cabbage in Reidsville. Cabbage head weight was highest when the crop was not preceded by SS in both CT and NT systems (1.6 as opposed to 1.3–1.4 kg head−1). Our findings suggest that the potential for growers to manage a cover crop also as a hay crop does exist; however, SS may not be a compatible cover crop species for organic fall cabbage production due to high amounts of re-growth.}, number={3}, journal={RENEWABLE AGRICULTURE AND FOOD SYSTEMS}, author={Finney, Denise M. and Creamer, Nancy G. and Schultheis, Jonathan R. and Wagger, Michael G. and Brownie, Cavell}, year={2009}, month={Sep}, pages={225–233} }
 @article{hill_hopkins_davidson_bolt_diaz_brownie_brown_huntington_whitlow_2009, title={The addition of cottonseed hulls to the starter and supplementation of live yeast or mannanoligosaccharide in the milk for young calves}, volume={92}, ISSN={["1525-3198"]}, DOI={10.3168/jds.2008-1320}, abstractNote={The objectives of this study were to investigate the effects of the addition of cottonseed hulls (CSH) to the starter and the supplementation of live yeast product (YST) or mannanoligosaccharide product (MOS) to milk, on growth, intake, rumen development, and health parameters in young calves. Holstein (n = 116) and Jersey (n = 46) bull (n = 74) and heifer (n = 88) calves were assigned randomly within sex at birth to treatments. All calves were fed 3.8 L of colostrum daily for the first 2 d. Holstein calves were fed 3.8 L of whole milk, and Jersey calves were fed 2.8 L of whole milk through weaning at 42 d. Calves continued on trial through 63 d. Six treatments were arranged as a 2 x 3 factorial. Calves received either a corn-soybean meal-based starter (21% crude protein and 6% acid detergent fiber; -CSH) or a blend of 85% corn-soybean meal-based starter and 15% CSH (18% crude protein and 14% acid detergent fiber; +CSH) ad libitum. In addition, calves received whole milk with either no supplement (NONE) or supplemented with 3 g/d of mannanoligosaccharide product (MOS) or 4 g/d of live yeast product (YST) through weaning at 42 d. Twelve Holstein steers [n = 6 (per starter type); n = 4 (per supplement type)] were euthanized for collection and examination of rumen tissue samples. Dry matter intake (DMI) was greater for Holstein calves fed +CSH (0.90 kg/d) than -CSH (0.76 kg/d). Final body weight at 63 d of Holstein calves fed +CSH (75.8 kg) was greater than that of those fed -CSH (71.0 kg). Average daily gain (ADG) was greater for Holstein calves fed +CSH (0.58 kg/d) than -CSH (0.52 kg/d). However, Holstein calves fed -CSH had a greater feed efficiency (FE; 0.71 kg of ADG/kg of DMI) than those fed +CSH (0.65 kg of ADG/kg of DMI). Also, Holstein calves fed +CSH had narrower rumen papillae (0.32 mm) compared with those fed -CSH (0.41 mm). There were no significant effects of CSH on DMI, ADG, or FE in Jersey calves. There were no significant effects of YST or MOS on DMI, ADG, FE, or rumen papillae measures in Holstein calves. Jersey calves fed YST or MOS had greater final body weight at 63 d (51.2 kg and 51.0 kg, respectively) than calves fed NONE (47.5 kg). However, there were no significant effects of YST or MOS on DMI, ADG, or FE in Jersey calves.}, number={2}, journal={JOURNAL OF DAIRY SCIENCE}, author={Hill, S. R. and Hopkins, B. A. and Davidson, S. and Bolt, S. M. and Diaz, D. E. and Brownie, C. and Brown, T. and Huntington, G. B. and Whitlow, L. W.}, year={2009}, month={Feb}, pages={790–798} }
 @article{benda_brownie_schal_gould_2009, title={Fruit abscission by Physalis species as defense against frugivory}, volume={130}, ISSN={["1570-7458"]}, DOI={10.1111/j.1570-7458.2008.00792.x}, abstractNote={AbstractFruit abscission as a response to herbivory is well‐documented in many plant species, but its effect on further damage by mobile herbivores that survive fruit abscission is relatively unstudied. Physalis plants (Solanaceae) abscise fruit containing feeding larvae of their main frugivore, Heliothis subflexa Guenée (Lepidoptera: Noctuidae), a specialist moth. We tested the ability of H. subflexa larvae placed under the plant canopy to find and climb onto two architecturally different Physalis species. Physalis pubescens L., a low, shrub‐like, spreading plant, abscises its fruit at a higher rate than Physalis angulata L., a tall arborescent plant. As a result, small larvae are more often dropped from P. pubescens. Third and fifth instars located P. pubescens faster and with a higher probability than P. angulata. Although fifth instars outperformed third‐instar caterpillars at finding P. angulata, P. pubescens was located equally fast by the two instars. Heliothis subflexa located Physalis plants more successfully and more quickly than a close relative, the generalist Heliothis virescens Fabricius. The higher fruit abscission rates in P. pubescens may be an evolved response to its greater susceptibility to searching caterpillars.}, number={1}, journal={ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA}, author={Benda, Nicole D. and Brownie, Cavell and Schal, Coby and Gould, Fred}, year={2009}, month={Jan}, pages={21–27} }
 @article{baynes_brownie_freeman_riviere_1996, title={In vitro percutaneous absorption of benzidine in complex mechanistically defined chemical mixtures}, volume={141}, ISSN={["0041-008X"]}, DOI={10.1006/taap.1996.0315}, abstractNote={Little work has been done on the topical absorption of the bladder carcinogen benzidine. Since humans are more likely to be exposed to chemical mixtures than to a single chemical, a program was developed in these laboratories to examine the cumulative effect of complex mixtures on percutaneous absorption of important toxicants such as benzidine. In this investigation, a mixture is defined as a physical combination consisting of a marker chemical and several other chemicals, each of which can have independent and/or synergistic effects on dermal penetration and absorption of the marker chemical. Ten mixtures, consisting of a marker chemical (benzidine, B), a solvent (acetone, A or DMSO, D), a surfactant (0 or 10% sodium lauryl sulfate, SL), a vasodilator (0 or 180 microg methyl nicotinate, M), and a reducing agent (0 or 2% SnCl2, s) were employed in this study. Isolated perfused porcine skin flaps (IPPSFs), which have proven to be a suitable in vitro model for assessing dermal absorption and toxicity, and flow-through diffusion cell systems were utilized. The extent of benzidine absorption in skin sections dosed with either B + A (0.94% dose) or B + D (1.01% dose) was similar to that when IPPSFs were dosed with either B + A (0.54% dose) or B + D (1.31% dose). However, flux vs time profiles were different when the two in vitro methods were compared. For mixtures containing (1) DMSO only or acetone only or (2) solvents containing SL + M, benzidine absorption was enhanced when compared with other mixtures. Compared to acetone, DMSO appears to enhance dermal penetration of benzidine in most of the mixtures. Compared to other mixtures evaluated, SnCl2 inhibited benzidine absorption irrespective of solvent present. SnCl2 also appears to inhibit benzidine penetration in DMSO mixtures containing SL only, but not in acetone mixtures. It is proposed that chemical-chemical interactions between benzidine and SnCl2 may be inhibiting benzidine absorption and chemical-biological interactions between M + SL and skin may be enhancing benzidine absorption. Across all mixtures, maximum observed benzidine absorption was almost 3% of the topical dose over 8 hr, but maximum penetration was 22% over the same time period which would suggest a potential for greater systemic exposure over longer time frames. This work underscores the need to study potentially toxic chemicals in mixture exposure scenarios since the interactions observed would confound risk assessment based on single chemical data.}, number={2}, journal={TOXICOLOGY AND APPLIED PHARMACOLOGY}, author={Baynes, RE and Brownie, C and Freeman, H and Riviere, JE}, year={1996}, month={Dec}, pages={497–506} }
 @article{brownie_bowman_burton_1993, title={ESTIMATING SPATIAL VARIATION IN ANALYSIS OF DATA FROM YIELD TRIALS - A COMPARISON OF METHODS}, volume={85}, ISSN={["0002-1962"]}, DOI={10.2134/agronj1993.00021962008500060028x}, abstractNote={AbstractIn large yield trials, variation in soil fertility (or, more generally, yield potential) can result in substantial heterogeneity within blocks and, thus, poor precision in treatment estimates. Precision may be improved using statistical analyses in which this spatial variation is accounted for in estimation of treatment or entry means. Three such types of spatial analysis are trend analysis, the Papadakis method, and analyses based on correlated errors models (which account for spatial variation through correlations between yields of neighboring plots). We reviewed the theory and empirical performance of these spatial analyses and compared them with the classical analyses. The classical analyses can be justified solely on the basis of randomization; spatial analyses depend on the model specified for the variation in yield potential. Performance depends on the polynomial used to describe yield potential in trend analysis, on the neighboring plots used to estimate fertility in the Papadakis analysis, and on the correlation structure in the correlated errors models. Empirical comparisons were based on data from 11 corn (Zea mays L.) yield trials and 1 soybean (Glycine max L.) trial, each showing evidence of heterogeneity within blocks. In comparison with the classical randomized blocks analysis, precision tended to be best for the trend and the trend plus correlated errors analyses, with the Papadakis method intermediate. Ranking of entries differed across analyses, because each analysis adjusts for spatial variation in a different way. Using a spatial analysis technique can improve precision, but selecting the most appropriate analysis for a given data set can be hard.}, number={6}, journal={AGRONOMY JOURNAL}, author={BROWNIE, C and BOWMAN, DT and BURTON, JW}, year={1993}, pages={1244–1253} }