Alternative to the use of synthetic nitrogen fertilizers can be the utilization of a natural organic source of on-farm animal manure nutrients for the growth, development and production of agricultural crops. The main objective of this research was to compost the poultry manure with organic amendments and utilize for sweet corn production. The composition of composted and uncomposted poultry manure was compared and field experiments were conducted during 2002 and 2004 at Randolph farm of Virginia State Univ. located near Petersburg, Virginia. The field experiments included seven treatments: control with un-composted manure, four treatments with manure (composted with wheat straw turned weekly, composted with wheat straw turned bi-weekly, composted with clover hay turned weekly, and composted with clover hay turned bi-weekly), recommended rate of N fertilizer, and a control without any treatment. Results indicated that composting of poultry manure with an organic amendment such as wheat straw or clover hay helps poultry manure's transformation into a usable fertilizer material for supporting crop production. However, use of clover hay was observed to be desirable than wheat straw for sweet corn production. Addition of clover hay resulted in significantly increased ear fresh and dry weight and also resulted in taller plants. The affects of biweekly vs. weekly turning compost on performance of sweet corn were not significant.
Muddappa Rangappa*, Harbans L. Bhardwaj and H.O. Dalton
K.M. Batal, M.R. Hall, D.M. Granberry, J.T. Garrett, D.R. Decoteau, R.T. Dufault, G.D. Hoyt, T.C. Gilsanz, J.M. Davis and D.C. Sanders
A vegetable production system using winter cover crops and N rates was evaluated for several years in Georgia, South Carolina, and North Carolina. Snap bean, cucumber, tomato, potato, and sweetpotato crops were tested at different locations. Cover crop plots produced higher yields and better quality in all locations as seasons progressed over 4 years. Soil N levels in fallow, wheat, and clover plots were similar at initiation, but N gradually increased in clover plots in successive years. Yield and quality of root crops improved with Crimson clover without N applications compared to fallow plots with 60 kg N/ha. Effects on yield and tuber size are discussed. Nitrate and NH4-N in the soil profile from 15- to 150-cm depth were monitored at all locations. Nitrogen availability, depletion, and leaching below the root zone were determined. At low N rate, clover plots had slightly higher NO3 in the soil profile; however, at high N rate, N supply by clover was not as critical, and N leaching was detected at much lower depths than at low N rates.
Kathryn E. Brunson and Sharad C. Phatak
Cantaloupe (Cucumis melo L., cv. Hiline) were planted following over-wintering cover crops. In replicated field trials, stand development for 7 different cover crops and their effects on incidence of weeds, insects, diseases, and nematodes was assessed. Effects of cover crops on yield and quality of cantaloupe were evaluated. Cover crops evaluated were rye, crimson clover, lentils, subterranean clover, `Vantage' vetch, mustard, a polyculture of all cover crops and control-fallow. No insecticides were applied and only two applications of fungicides were made. Fertilizer applications were significantly reduced. No differences among cover crops for any of pest nematodes were observed. Significant differences in populations of beneficial and pest insects were observed. Polyculture had the highest plant vigor rating. The highest marketable yield occurred following crimson clover.
Owusu A. Bandele, Marion Javius, Byron Belvitt and Oscar Udoh
Fall-planted cover crops of hairy vetch (Vicia villosa Roth), Austrian winter pea (Pisum sativum subsp. arvense L. Poir), and crimson clover (Trifolium incarnatum L.) were each followed by spring-planted 'Sundance' summer squash [Cucurbita pepo var. melopepo (L.) Alef.] and 'Dasher' cucumber (Cucumis sativus L.). Squash and cucumber crops were followed by fall 'Florida Broadleaf mustard green [Brassica juncea (L.) Czerniak] and 'Vates' collard (Brassica oleracea L. Acephala group), respectively. The same vegetable sequences were also planted without benefit of cover crop. Three nitrogen (N) rates were applied to each vegetable crop. Squash following winter pea and crimson clover produced greater yields than did squash planted without preceding cover crop. Cucumber following crimson clover produced the greatest yields. No cover crop effect was noted with mustard or collard. Elimination of N fertilizer resulted in reduced yields for all crops, but yields of crops with one-half the recommended N applied were generally comparable to those receiving the full recommended rate.
D.C. Sanders, G.D. Hoyt, J.C. Gilsanz, J.M. Davis, J.T. Garrett, D.R. Decoteau, R.J. Dufault and K.D. Batal
`Jewel' sweetpotato was no-till planted into crimson clover, wheat, or winter fallow. Then N was applied at 0, 60, or 120 kg·ha–1 in three equal applications to a sandy loam soil. Each fall the cover crop and production crop residue were plowed into the soil, beds were formed, and cover crops were planted. Plant growth of sweetpotato and cover crops increased with N rate. For the first 2 years crimson clover did not provide enough N (90 kg·ha–1) to compensate for the need for inorganic N. By year 3, crimson clover did provide sufficient N to produce yields sufficient to compensate for crop production and organic matter decomposition. Soil samples were taken to a depth of 1 m at the time of planting of the cover crop and production crop. Cover crops retained the N and reduced N movement into the subsoil.
Greg D. Hoyt
An experiment was established to determine the effect of different winter cover crops residues on yields of no-till pumpkins, yellow summer squash, and sweet corn. Residue treatments of fallow, triticale, crimson clover, little barley, and crimson clover + little barley were fall established and killed before spring no-till planting in 1998 and 1999. All summer vegetables received recommended fertilizer rates and labeled pesticides. Spring cover crop growth and biomass measurements ranged from 1873 to 6362 kg/ha. No-till sweet corn yields among the various cover residue treatments were greater where crimson clover and crimson clover + little barley (mixture) were used as residue in 1999, but not significantly different in 1998. No-till pumpkins showed the beneficial affect cover crop residue had on vegetable yields when dry conditions exist. Triticale and crimson clover + little barley (mixture) residues reduced soil water evaporation and produced more numbers of fruit per hectare (5049 and 5214, respectively) and greater weights of fruit (20.8 and 20.9 Mg/ha) than the other residue treatments (3725 to 4221 fruit/ha and 11.8 to 16.1 Mg/ha, respectively). No-till summer squash harvest showed steady increases in yield through time by all treatments with crimson clover residue treatment with the greatest squash yields and triticale and little barley residue treatments with the lowest squash yields. We found that sweet corn and squash yields were greater where legume cover residues were used compared to grass cover residues, whereas, pumpkin yields were higher where the greatest quantity of mulch was present at harvest (grass residues).
Carlene A. Chase and Odemari S. Mbuya
Living mulches between beds of polyethylene-mulched vegetable crops may suppress weeds and decrease surface and ground water contamination by pesticides. They should be either low growing or amenable to mowing and should withstand traffic. Twelve winter cover crops were planted in north (N.) and north central (N.C.) Florida in Fall 2004: black oats (Avena strigosa cv. Soilsaver), annual ryegrass (Lolium multiflorum cv. Gulf), rye (Secale cereale cv. Wrens Abruzzi), hard fescue (Festuca longifolia cv. Oxford), white clover (Trifolium repens cvs. Dutch white and New Zealand white), berseem clover (T. alexandrinum cv. Bigbee), crimson clover (T. incarnatum cv. Dixie), subterranean clover (T. subterraneum cv. Mt. Barker), arrowleaf clover (T. vesiculosum cv. Yuchi), a barrel medic (Medicago trunculata cv. Parabinga), and a disc × strand medic (M. tornata × M. littoralis cv. Toreador). Black oats, rye, and annual ryegrass established quickly and suppressed winter annual weeds. Canopy development of the other species was poor. Shoot biomass was greater in N. Florida than in N.C. Florida. The highest shoot biomass occurred with black oats. By 8 weeks after planting (WAP) rye and annual ryegrass had similar amounts of biomass, but by 16 WAP the yield of rye was greater. At some harvests, biomass with wheel traffic or mowing was lower than without, but black oats, rye, and ryegrass did not succumb to these treatments. Of the legumes, only crimson clover and `Toreador' medic in N. Florida produced sufficient biomass by 16 WAP to permit a harvest. Black oats, rye, and annual ryegrass appear to be the best living mulch candidates; however, black oats would require more frequent mowing.
Natalie R. Bumgarner, Mark A. Bennett, Peter P. Ling, Robert W. Mullen and Matthew D. Kleinhenz
raised bed frame to contain the medium. The growing medium consisted of (v/v) 35% peat (Premier Horticulture, Quakerstown, PA), 35% dairy manure compost (OARDC), 15% shredded organic red clover hay (OARDC), and 15% silt loam field soil (OARDC). A mixer
Kathryn E. Brunson, Sharad C. Phatak, C. Robert Stark Jr. and Michael E. Wetzstein
Research results are presented of a multi-year study on eggplant in Southern Georgia comparing two sustainable production technologies to the conventional rye cover crop technology. The sustainable technologies utilize beneficial insect principles as a substitute for conventional pesticide controls. Preliminary results from the sustainable technologies using crimson clover and subterranean clover indicate that the higher yields under rye can be more than offset by cost reductions associated with selected sustainable technologies. Production budgets are developed for eggplant to indicate expected net returns under both the sustainable and conventional technologies
Dennis R. Decoteau, J.M. Davis, G.D. Hoyt, K.M. Batal, D.C. Sanders, J.T. Garrett and R.J. Dufault
A 5-year study using winter cover crops (wheat or rye, crimson clover, and fallow) in a tomato and bean rotation indicated several soil responses to the cover crops. Advantages of crimson clover winter cover crop to the soil in a tomato-bean rotation included adding organic matter to the soil, which resulted in an increase in the amount of inorganic nitrogen in the upper levels of the soil profile and an increase in the soil's water-holding capacity. An additional benefit of winter cover crops to the soil was the potential of reduced nitrogen leaching.