Crop covers

Study 1. Wheat ( McNair 1813 ) was planted at the Central Crops Research Station near Clayton (Lynchburg sandy loam) and the Tidewater Research Station near Plymouth (Bayboro loam), North Carolina, at a rate of 101 kg/ha in October of 1980. The following spring or early summer, plots were set up in which a green wheat cover crop or wheat straw and stubble remaining after wheat harvest was (1) left... 

Study 2. The effects of wheat, oats, barley and rye mulches on three broadleaf weed species and crabgrass (Digitaria spp.) are shown in Table VI. Weed control data for the corn test at Kinston are not presented because of poor cover crop kill by the paraquat treatment. 

Corn test at Kinston abandoned due to poor cover crop kill with paraquat. 

It is unlikely that any one particular compound could be responsible for reduced weed growth in no-till. Higher plants and microorganisms produce a myriad of phytotoxic substances. If these substances are present in the right combination and concentration, phytotoxic effects may be observed. With the proper choice and management of various cover crops and plant residues, it may be possible to supplement if not reduce the number and amount of... 

Meisinger, J.J., Hargrove, W.L., Mikkelsen, R.L., Williams, J.R., and Benson, V.W., Effects of cover crops on groundwater quality, in Cover Crops for Clean Water, Hargrove, W.L., Ed., Soil Conservation Society, 1991, pp. 57-68. 

Crop rotation using a range of contrasting crops (including cover crops or a period of fallow) can decrease soilborne pathogen inocula, increase diversity in soil microflora over time and be unfavourable for the of spread foliar diseases in the shorter term. This reduces the need for pesticides. 

Cover crops Improves fertility Improves water availability Nutrient recycling Reduces costs Soil erosion and runoff control Weed control Kalinova (2009) Malezieux et al. (2009) Pati et al. (2009) Runyon et al. (2009) Stagnari et al. (2009) Wu and Sardo (2009) Zuazo and Pleguezuelo (2009)... 

Peachey RE, Pinkerton JN, Ivors KL, Miller ML, Moore LW (2001) Effect of soil solarization, cover crops, and metham on field emergence and survival of buried annual bluegrass (Poa annua) seeds. Weed Technol 15 81-88... 

The transition from conventional to organic and low-input farming is accompanied by changes in an array of soil chemical properties and processes that affect soil fertility. Fundamental differences, both qualities and quantitative, in the flow and processing of nutrient result from the use of cover crops, manure and compost applications, and reduction or elimination of synthetic fertilizers and pesticides. These changes affect nutrient availability to crops either directly by contributing to nutrient pools or indirectly by influencing the soil chemical and physical environment. 

Soil erosion Too much plowing/tilling, no cover crops... 

Keywords Allelopathy Cover crops Crop residues Intercropping Mulching Organic farming Weeds... 

Allelopathic interactions of plants can provide weed control by (a) use of allelopathic crops as cover crops, mulches or green manure, (b) use of allelopathic plants in crop rotations, (c) crop mixtures and intercropping, (d) varieties with strong allelopathic potential, and (e) use of allelopathic crop water extracts and other agents. 

Fig. 14.2 Well established stand of common buckwheat as a cover crop has great weed suppressive effects. Buckwheat emits allelochemicals, thus controlling weeds... 

Providing weed suppression through the use of allelopathic cover crops is an important method of weed control in organic farming and it is one of the best possibilities of allelopathy application (Sullivan 2003a). Besides, growing of cover... 

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