Screening cool-season legume cover crops for pecan orchards

1994 ◽  
Vol 9 (3) ◽  
pp. 127-134 ◽  
Author(s):  
Michael W. Smith ◽  
Raymond D. Eikenbary ◽  
Don C. Arnold ◽  
B. Scott Landgraf ◽  
Glenn G. Taylor ◽  
...  

AbstractWe evaluated selected cool-season annual and perennial legumes as potential ground covers to supply nitrogen and to increase beneficial arthropod populations in a pecan orchard. Densities of aphids (Homoptera: Aphididae), lady beetles (Coleoptera: Coccinellidae), damsel bug (Hemiptera: Nabidae), green lacewings (Neuroptera: Chrysopidae), brown lacewings (Neuroptera: Hemerobiidae), hover flies (Diptera: Syrphidae), spined soldier bug and other stink bugs (Hemiptera: Pentatomidae), and spiders (Araneida) were monitored at 7–14 day intervals during the growing season for three years. Aboveground biomass production and nitrogen content of the legumes was measured for two years. Aphids peaked during early spring each year, with the highest density usually on ‘Dixie’ crimson clover and ‘Kenland’ red clover. Density of lady beetles was positively correlated with that of aphids, but spider densities were not. Other arthropods usually were not abundant. Nitrogen in the tops of the annual legumes ranged from 20 kg/ha to 89 kg/ha when assessed after a single harvest at anthesis; for the perennial legumes it was from 108 kg/ha to 179 kg/ha following two harvests in June and September. We chose two annual legumes (‘Dixie’ crimson clover and hairy vetch) and two perennial legumes (‘Louisiana S-1’ white clover and ‘Kenland’ red clover) for further evaluation.

2020 ◽  
Vol 100 (3) ◽  
pp. 179-188
Author(s):  
X.M. Yang ◽  
C.F. Drury ◽  
W.D. Reynolds ◽  
L.A. Phillips

Nitrogen (N) release from legume cover crops is a key N source for subsequent crops in rotation. In this study, chopped fresh shoots or roots (<5 mm) of crimson clover (CC), hairy vetch (HV), and red clover (RC) were incorporated into a 50:50 mixture of air-dried sandy loam soil (<2 mm) and washed builders sand at a rate of 300 mg N kg−1. The mixtures were packed in leaching tubes (four replicates), leached with 100 mL of 5 mmol L−1 CaCl2, and then incubated for 10 wk (22 °C, 0.33 bar matric potential) with weekly leaching. Total N and inorganic N (NH4+ plus NO3−) in leachate were quantified and organic N was determined as the difference between total N and inorganic N. More N was released from shoots (63.4%–70.0% of initial N) than from roots (27.3%–50.7% of initial N). Mineralized organic N and inorganic N followed the first order, single N-pool mineralization model [Nt = N0(1 – e−kt); R2 = 0.94−0.99]. Potentially mineralizable N (N0, as % of initial N) was similar for shoots (CC = 75.1%, HV = 74.2%, and RC = 71.3%), but varied for roots (CC = 36.2%, HV = 52.6%, and RC = 53.0%). The N0 pool in shoots had a half-life (t1/2 = ln 2/k) of 11.0, 9.8, and 15.1 d for CC, HV, and RC, respectively; and a half-life in roots of 23.9, 8.5, and 25.7 d, respectively. Hence, HV released its stored N in both roots and shoots faster than CC and RC. The results in this study would help farmers optimize their choice in legume cover crops and termination times to better synchronize N release with crop uptake.


1988 ◽  
Vol 34 (3) ◽  
pp. 201-206 ◽  
Author(s):  
C. S. Rothrock ◽  
W. L. Hargrove

The influence of winter legume cover crops and of tillage on soil populations of fungal genera containing plant pathogenic species in the subsequent summer sorghum crop were examined in field studies. Legume cover crops significantly increased populations of Pythium spp. throughout the sorghum crop compared with a rye cover crop or no cover crop. This stimulation of the populations of Pythium spp. was not solely due to colonization of cover-crop residue, as populations were significantly greater at the time the legume cover crop was desiccated. Removal of aboveground residue generally decreased populations of Pythium spp. in soil. Incorporation of residue by tillage increased populations of Pythium spp. at some sampling dates. Legumes differed in the magnitude of stimulation, with hairy vetch stimulating Pythium spp. more than crimson clover. Cover crop treatments did not consistently influence soil populations of Fusarium spp., Rhizoctonia solani, Rhizoctonia-like binucleate fungi, or Macrophomina phaseolina. Macrophomina phaseolina populations were significantly greater under no tillage.


2018 ◽  
Vol 32 (3) ◽  
pp. 227-235 ◽  
Author(s):  
Matheus G. Palhano ◽  
Jason K. Norsworthy ◽  
Tom Barber

AbstractCover crop acreage has substantially increased over the last few years due to the intent of growers to capitalize on federal conservation payments and incorporate sustainable practices into agricultural systems. Despite all the known benefits, widespread adoption of cover crops still remains limited due to potential cost and management requirements. Cover crop termination is crucial, because a poorly controlled cover crop can become a weed and lessen the yield potential of the current cash crop. A field study was conducted in fall 2015 and 2016 at the Arkansas Agricultural Research and Extension Center in Fayetteville to evaluate preplant herbicide options for terminating cover crops. Glyphosate-containing treatments controlled 97% to 100% of cereal rye and wheat, but glyphosate alone controlled less than 57% of legume cover crops. The most effective way to control hairy vetch, Austrian winterpea, and crimson clover with glyphosate resulted from mixtures of glyphosate with glufosinate, 2,4-D, and dicamba. Higher rates of auxin herbicides improved control in these mixtures. Glufosinate alone or in mixture controlled legume cover crops 81% or more. Paraquat plus metribuzin was effective in terminating both cereal and legume cover crops, with control of cereal cover crops ranging from 87% to 97% and control of legumes ranging from 90% to 96%. None of these herbicides or mixtures adequately controlled rapeseed.


1990 ◽  
Vol 25 (3) ◽  
pp. 463-474 ◽  
Author(s):  
Robert L. Bugg ◽  
Felix L. Wäckers ◽  
Kathryn E Brunson ◽  
Sharad C. Phatak ◽  
James D. Dutcher

Replicated field trials indicated that tarnished plant bug (TPB), Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae) attained relatively-high densities on hybrid vetches, Vicia sativa L. X V. cordata Wulf cv ‘Cahaba White’ and ‘Vantage’, lower densities on crimson clover, Trifolium incarnatum L. cv ‘Dixie,’ and particularly-low densities on subterranean clover, Trifolium subterraneum L. cv ‘Mt. Barker’. Densities of TPB were also relatively low on an additional 10 types of subterranean clover, including 7 cultivars representing T. subterraneum, 1 cultivar of T. brachycalycinum Katznelson and Morley, and 3 of T. yanninicum Katznelson and Morley. Field longevity trials indicated that late-instar and adult TPB lived longer when caged on crimson clover than on hybrid vetch, which in turn supported better survival than did subterranean clover. When adult TPB were caged on hybrid vetch or subterranean clover with or without floral and fruiting structures, there was no evidence that the presence of these structures prolonged TPB survival on either crop. In laboratory choice tests with flowering and fruiting shoots of three cover crops, TPB preferred crimson clover over hybrid vetch, which in turn was more attractive than subterranean clover. When shoots were presented after reproductive structures had been excised, there was no statistically-significant preference by TPB.


2016 ◽  
Vol 30 (2) ◽  
pp. 415-422 ◽  
Author(s):  
Matthew S. Wiggins ◽  
Robert M. Hayes ◽  
Lawrence E. Steckel

Glyphosate-resistant (GR) weeds, especially GR Palmer amaranth, are very problematic in cotton-producing areas of the midsouthern region of the United States. Growers rely heavily on PRE residual herbicides to control Palmer amaranth since few effective POST options exist. Interest in integrating high-residue cover crops with existing herbicide programs to combat GR weeds has increased. Research was conducted in 2013 and 2014 in Tennessee to evaluate GR Palmer amaranth control when integrating cover crops and PRE residual herbicides. Cereal rye, crimson clover, hairy vetch, winter wheat, and combinations of one grass plus one legume were compared with winter weeds without a cover crop followed by fluometuron or acetochlor applied PRE. Biomass of cover crops was determined prior to termination 3 wk before planting. Combinations of grass and legume cover crops accumulated the most biomass (> 3,500 kg ha−1) but by 28 d after application (DAA) the cereal rye and wheat provided the best Palmer amaranth control. Crimson clover and hairy vetch treatments had the greatest number of Palmer amaranth. These cereal and legume blends reduced Palmer amaranth emergence by half compared to non–cover-treated areas. Fluometuron and acetochlor controlled Palmer amaranth 95 and 89%, respectively, at 14 DAA and 54 and 62%, respectively, at 28 DAA. Cover crops in combination with a PRE herbicide did not adequately control Palmer amaranth.


2014 ◽  
Vol 94 (4) ◽  
pp. 771-783 ◽  
Author(s):  
Harun Cicek ◽  
Martin H. Entz ◽  
Joanne R. Thiessen Martens ◽  
Paul R. Bullock

Cicek, H., Entz, M. H., Thiessen Martens, J. R. and Bullock, P. R. 2014. Productivity and nitrogen benefits of late-season legume cover crops in organic wheat production. Can. J. Plant Sci. 94: 771–783. When full-season cover crops are used in stockless organic rotations, cash crop production is compromised. Including winter cereals in rotations can widen the growing season window and create a niche for late-season cover crops. We investigated the establishment and biomass production of relay-cropped red clover (Trifolium pratense L.) and sweet clover (Melilotus officinalis L. ‘Norgold’) and double-cropped cowpea (Vigna unguiculata L. ‘Iron and Clay’), hairy vetch (Vicia villosa L.), lentil (Lens culinaris L. ‘Indianhead’), soybean (Glycine max L. ‘Prudence’), pea (Pisum sativum L. ‘40-10’), and oil seed radish (Raphanus sativus L.) as well as wheat response to these crops under reduced tillage (RT) and conventional tillage (CT) at three locations in Manitoba, Canada. Red clover, sweet clover and pea produced from 737 to 4075 and 93 to 1453 and 160 to 2357 kg ha−1of biomass, respectively. All double crops, with the exception of soybean at 2 site years, established successfully under both RT and CT. The presence of cover crops increased wheat N uptake at stem elongation, maturity and yield, even when the biomass production of cover crops was modest. We conclude that late-season cover crops enhance the following wheat yield and facilitate reduced tillage in organic crop production.


2005 ◽  
Vol 85 (3) ◽  
pp. 645-648 ◽  
Author(s):  
J. R. Thiessen Martens ◽  
M. H. Entz ◽  
J. W. Hoeppner

Yield benefits of legume cover crops in winter/spring cereal systems have not been well documented in the Canadian prairies. The objective of this study was to evaluate the fertilizer replacement values (FRV) of relay-cropped alfalfa (Medicago sativa L.) and red clover (Trifolium pratense L.) and double-cropped chickling vetch (Lathryus sativus L.) and black lentil (Lens culinaris Medik. subsp. culinaris) to a subsequent oat (Avena sativa L.) crop. Field experiments were conducted in Manitoba on a clay soil at Winnipeg and a sandy loam at Carman. Alfalfa provided the highest FRV at Winnipeg (51–62 kg N ha-1), followed by chickling vetch (29–43 kg N ha-1), lentil (23–39 kg N ha-1), and red clover (24–26 kg N ha-1). FRV could not be established at Carman, where course-textured soil and low rainfall limited legume growth. Key words: Relay cropping, double cropping, cover crops


1990 ◽  
Vol 4 (2) ◽  
pp. 332-336 ◽  
Author(s):  
James L. Griffin ◽  
Seth M. Dabney

Field studies were conducted to compare preplant-postemergence-applied paraquat, glyphosate, SC-0224, and HOE-39866 on subterranean clover, crimson clover, and hairy vetch cover crops. Subterranean clover control with paraquat at 1.1 kg ai/ha was about 80 and 100% when applied in early April and early May, respectively, regardless of spray volume (190 vs. 370 L/ha). Glyphosate and SC-0224 at 1.7 and 2.8 kg ai/ha applied in April controlled about 53% of subterranean clover. Subterranean clover control with HOE-39866 at 0.8 kg ai/ha applied in April was excellent. Paraquat at 0.6 kg ai/ha and HOE-39866 at 0.8 kg/ha regardless of application time controlled both crimson clover and hairy vetch. Grain sorghum and soybean yields following the legume cover crops generally were similar for the herbicide treatments.


2002 ◽  
Vol 12 (2) ◽  
pp. 245-249 ◽  
Author(s):  
M. Rangappa ◽  
A.A. Hamama ◽  
H.L. Bhardwaj

Although there is increasing interest in reducing the use of nitrogen (N) fertilizers due to the potential of unused N causing pollution of surface and groundwater, N is a major nutrient for plant growth. Our objective was to determine the potential of using winter legume cover crops to meet the N needs of seedless watermelon (Citrullus lanatus), a potential cash crop for farmers in Virginia. Fruit number, fruit weight, fruit yield, and fruit quality traits (flesh to rind ratio, water content, total soluble solids, sugar content, and pH) of seedless watermelons were evaluated in replicated experiments in Virginia at three locations during 1997-98 and two locations during 1998-99 following cover crop treatments consisting of crimson clover (Trifolium incarnatum), hairy vetch (Vicia villosa), crimson clover + rye (Secale cereale), hairy vetch + rye, and a bareground control treatment that received 100 lb/acre (112 kg·ha-1) of N. At all five locations, the bareground control treatment resulted in fewer fruit [1803 fruit/acre (4454 fruit/ha)], lower fruit weight [9.8 lb (4.5 kg)], and lower fruit yield [8.9 tons/acre (20.0 t·ha-1)] compared to the four cover crop treatments. The crimson clover + rye and hairy vetch treatments resulted in highest numberof fruit [2866 and 2657 fruit/acre (7079 and 6563 fruit/ha), respectively], whereas the highest fruit yield was obtained following hairy vetch [21.2 tons/acre (49.8 t·ha-1)], hairy vetch + rye [20.3 tons/acre (45.5 t·ha-1)], and crimson clover + rye [19.6 tons/acre (43.9 t·ha-1)]. Cover crop treatments did not affect the quality of watermelon flesh. The seedless watermelon fruit averaged 1.4 flesh: 1 rind ratio, 90% water content, 9.5% total soluble solids, 8.0% sugar, and a pH value of 5.9. These results indicated that legume cover crops, such as crimson clover and hairy vetch, can be successfully used to produce seedless watermelons, in a no-till system, without any use of N fertilizers with dryland conditions.


1991 ◽  
Vol 6 (2) ◽  
pp. 50-62 ◽  
Author(s):  
Robert L. Bugg ◽  
Marianne Sarrantonio ◽  
James D. Dutcher ◽  
Sharad C. Phatak

AbstractAnnual legumes and mixtures of annual legumes and grasses can perform several functions as understory cover crops in pecan orchards, such as providing nitrogenrich organic matter to improve soil fertility, or by sustaining lady beetles and other arthropods that may aid the biological control of pecan pests. Remaining questions concern selection of appropriate plant materials; whether to use cover crops singly or in mixtures; how to ensure reseeding as well as a substantial N contribution; whether, when, and how to use mowing and tillage; and fertilization options. Different considerations apply when dealing with cool- vs. warm-season cover crops. With minor adjustments, growers could adapt present cultural practices to include cool-season cover crops. These could be used throughout the orchard, by establishing appropriate self-reseeding species and avoiding both excessive mowing and indiscriminate placement of N-rich fertilizers. Within alleys, alternating 2-m strips of cool-season cover crops could be tilled in mid to late April or allowed to mature. The tilled strips would supply N to pecan trees immediately, whereas the adjoining untilled (remnant) strips could be mowed after seed is mature, to ensure dispersal of seed and reestablishment of cover crops over the entire alley. Cool-season annual legumes that die or are killed in late spring will probably furnish N and other nutrients at a suitable time, particularly in orchards with sprinkler irrigation. Warm-season cover crops, if desired, should be restricted to alleys to reduce possible competition with pecan. Alleys provide better illumination than do tree rows during periods when pecan trees are in leaf, and the tillage mentioned above will encourage emergence of warm-season cover crops. If these die or are killed in late summer or early fall, timing of N release may not be optimal, in the absence of adequate irrigation. Many options and tradeoffs need to be explored before choosing a cover-crop system. Attimes, several objectives may appear to conflict, and even delicately-managed mixtures of species may not fulfill all the desired functions.


Sign in / Sign up

Export Citation Format

Share Document