@article{burns_chamblee_giesbrecht_2002, title={Defoliation intensity effects on season-long dry matter distribution and nutritive value of tall fescue}, volume={42}, ISSN={["0011-183X"]}, DOI={10.2135/cropsci2002.1274}, abstractNote={Implementation of intensive grazing management requires knowledge about pasture growth rates and nutritive value throughout the grazing season. Such information is lacking because results from small-plot defoliation experiments generally focus on annual dry matter yields (DMYs) and season mean nutritive value. In this experiment, the influences of defoliation treatments on daily growth rate (DGR) and associated nutritive value of tall fescue (Festuca arundinacea Schreb.) throughout the growing season were evaluated. A 3-yr study was conducted on a Typic Kanhapludult soil near Raleigh, NC. Eight defoliation treatments (31-, 15-, 10- and 8-cm canopy heights cut to a 5-cm stubble; 31-, 15-, and 11-cm canopy heights cut to a 9-cm stubble, and an 8-cm canopy height cut to a 4-cm stubble) were evaluated in a randomized complete block design. Daily growth rates (kg ha -1 ) were significantly (P ≤ 0.01) altered by defoliation treatments and by years within treatments. When rainfall was near normal in both spring and late summer, tall fescue growth rates, depending on defoliation treatment, ranged from 34 to 55 kg ha -1 d -1 in May, from 7 to 18 kg ha -1 d -1 in late July, to 22 to 35 kg ha -1 d -1 in late September. In less favorable years, DGRs seldom exceeded 30 kg ha -1 d -1 in the spring or 15 to 30 kg ha -1 d -1 in the autumn. Depending on defoliation treatments, in vitro dry matter disappearance (IVDMD) ranged between 650 and 733 g kg -1 in the spring, 479 and 687 g kg -1 in midsummer, and 549 and 807 g kg -1 by late summer. Crude protein (CP) and detergent fiber fraction concentrations were also examined. The approach used to estimate DGR and associated nutritive value changes throughout the growing season resulted in useful data that can be applied in developing intensive grazing management practices.}, number={4}, journal={CROP SCIENCE}, author={Burns, JC and Chamblee, DS and Giesbrecht, FG}, year={2002}, pages={1274–1284} } @article{burns_chamblee_2000, title={Summer accumulation of tall fescue at low elevations in the Piedmont: I. Fall yield and nutritive value}, volume={92}, ISSN={["0002-1962"]}, DOI={10.1007/s100870050024}, number={2}, journal={AGRONOMY JOURNAL}, author={Burns, JC and Chamblee, DS}, year={2000}, pages={211–216} } @article{burns_chamblee_2000, title={Summer accumulation of tall fescue at low elevations in the humid Piedmont: II. Fall and winter changes in nutritive value}, volume={92}, ISSN={["1435-0645"]}, DOI={10.1007/s100870050025}, number={2}, journal={AGRONOMY JOURNAL}, author={Burns, JC and Chamblee, DS}, year={2000}, pages={217–224} } @book{belesky_burns_chamblee_daniel_ruiter_fisher_green_mochrie_mueller_pond_et al._1998, title={Carostan flaccidgrass: Establishment, adaption, production management, forage quality, and utilization}, publisher={Raleigh, NC: N.C. Agricultural Research Service, N.C. State University}, author={Belesky, D. P. and Burns, J.C. and Chamblee, Douglas S. and Daniel, Dorsey W. and Ruiter, J.M. and Fisher, D.S. and Green, J. T. and Mochrie, R. D. and Mueller, J. P. and Pond, K. R. and et al.}, year={1998} } @article{burns_chamblee_belesky_fisher_timothy_1998, title={Nitrogen and defoliation management: Effects on yield and nutritive value of flaccidgrass}, volume={90}, DOI={10.2134/agronj1998.00021962009000010016x}, abstractNote={Abstract‘Carostan’ flaccidgrass (Pennisetum flaccidum Griseb.), a C4 perennial grass, has shown high quality potential in animal trials. Its yield response to defoliation frequency and N fertilization, however, has not been reported. We examined the influence of stubble height and of a range of N applications in two defoliation experiments over 4 yr. Experiment 1 (Raleigh, NC) combined two harvest heights, 76 and 38 cm, with two stubble heights, 25 and 15 cm (76–25, 76–15, 38–25, 38–15); all treatments received 380 kg N ha−1 yr−1. After Year 1, the 76–15 defoliation produced higher yields than 76–25 (Year 2: 11 330 vs. 7930 kg ha−1, P < 0.001; Year 3:8950 vs. 6270 g kg−1, P < 0.001), while in vitro dry matter disappearance (IVDMD) was similar (Year 3) (mean = 582 g kg−1). Compared with 38–15, the 38–8 defoliation resulted in lower yields (Year 2: 8638 vs. 9344 kg ha−1, P = 0.001; Year 3, 6173 vs. 8090 kg ha−1, P = 0.07) but higher IVDMD (Year 3, 651 vs. 635 g kg−1, P < 0.01). Experiment 2 (Raleigh, NC, and Watkinsville, GA) had four defoliations: clipping to 5 cm at 20 and 51 cm (vegetative) and to 8 cm at boot and anthesis stages (20–5, 51–5, Boot—8, Anthesis—8). All defoliation treatments were topdressed with 291 kg N ha−1, and 51–5 and Boot—8 were also evaluated with 179 and 403 kg N ha−1 (eight N—defoliation treatments in all). At both locations, highest yields were obtained with Anthesis—8, averaging 19 010 kg ha−1 at Raleigh and 12 390 kg ha−1 at Watkinsville. The 20–5 defoliation resulted in lowest yields at both locations, averaging 7648 kg ha−1 at Raleigh and 5100 kg ha−1 at Watkinsville. Defoliation frequency altered IVDMD (range = 550 to 789 g kg−1), but N application did not; however, increasing N application increased N concentrations linearly (P = 0.05). Flaccidgrass had high yield potential and high nutritive value at the Raleigh location, and warrants further evaluation in the upper South.}, number={1}, journal={Agronomy Journal}, author={Burns, J. C. and Chamblee, D. S. and Belesky, D. P. and Fisher, D. S. and Timothy, D. H.}, year={1998}, pages={85–92} } @article{chamblee_warren_1990, title={MOVEMENT OF RHIZOBIA BETWEEN ALFALFA PLANTS}, volume={82}, ISSN={["1435-0645"]}, DOI={10.2134/agronj1990.00021962008200020021x}, abstractNote={AbstractEvidence on the rapidity of movement of rhizobia in the soil is inconclusive. Successful inoculation of most of the legume plants in a field would result in subsequent inoculation of the remaining plants if substantial movement of legume bacteria occurred. The objective of this study was to determine the distance rhizobia move in the soil between inoculated and noninoculated alfalfa (Medicago sativa L.) plants during the seeding year. Three field experiments were conducted in North Carolina. Experiments 1 and 2 were established on a Norfolk sandy loam (fine‐loamy, siliceous thermic Typic Paleudult) and Exp. 3 on an Appling sandy loam (kaolinitic thermic Typic Hapludult). Alternating rows of inoculated and noninoculated alfalfa (subplots) were seeded at spacings of 15,30 and 60 cm (whole plots) in four replications. Periodic measurements of nodulation, color, height of top growth and N concentration of top growth and roots were made. Results indicated that the lateral movement of rhizobia in an 11‐month period was largely limited to a distance of 15 cm. There was evidence that substantial N was obtained by noninoculated alfalfa rows from adjacent inoculated (15‐cm spacing) rows by sloughing and/or excretion.}, number={2}, journal={AGRONOMY JOURNAL}, author={CHAMBLEE, DS and WARREN, RD}, year={1990}, pages={283–286} }