Introduction Organic production rose to 2.3 million acres in the U.S. in 2001 (USDA-ERS, 2002). Much of the increase has been associated with the implementation of consistent federal standards for products marketed as “organic” in October 2002 (USDA/AMS, 2002). In order to meet certified organic requirements in the state of Iowa (IDALS, 2000), a soilbuilding cover crop is required for at least ...

One of the principal aims of alternative cropping systems is to minimize excessive loss of N while maximizing N use efficiency and meeting crop N requirements. Many such cropping systems substitute intensive application of synthetic fertilizer with organic inputs, such as N2-fixing legumes. The effectiveness of legume residues as a N source for subsequent crops depends heavily on temporal N rel...

Soil carbon (C) sequestration in tilled and nontilled areas can be influenced by crop management practices due to differences in plant C inputs and their rate of mineralization. We examined the influence of four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secale cereale L.)], biculture of legume and nonlegume (vetch and rye), and no cover crops (or winter weeds)} and...

Vegetable production is heavily dependent upon high off-farm inputs of polyethylene (plastic) mulch, nitrogen fertilizer and pesticides. Such a production practice potentially contributes to the unintentional environmental pollution with fertilizer and pesticides as well as water run off and soil erosion. This raises serious environmental concerns for human and animal health. The integration of...

Producers are interested in tactics for managing crop residues when growing corn after spring wheat. We compared five systems of managing spring wheat residues: conventional tillage, no-till, strip-till, cover crop (hairy vetch) with no-till, and cover crop with strip-till following spring wheat. Conventional tillage consisted of chisel plowing and disking, whereas strip-till consisted of tilli...

Weed management is a major issue in organic farming systems. Although interseeding cover crops is one alternative to herbicides, cover crops often suppress not only weeds but also main crops. Therefore, using cover crops for weed control without adverse effects on main crop growth is important. To verify the effect of cover crops on competition between main crops, cover crops and weeds in snowy...

Hairy vetch is a leguminous winter annual cover crop that provides a significant contribution toward meeting the nitrogen requirement of succeeding crops. Hairy vetch residue is capable of suppressing weeds, but low levels of residue can intermittently stimulate the emergence of weeds, particularly smooth pigweed. This research was conducted to assess the inhibitory and stimulatory effects of h...

Fusarium head blight, caused by fungi from the genus Fusarium, is one of the most harmful cereal diseases, resulting not only in severe yield losses but also in mycotoxin contaminated and health-threatening grains. Fusarium head blight is caused by a diverse set of species that have different host ranges, mycotoxin profiles and responses to agricultural practices. Thus, understanding the compos...

As the name implies, a cover crop consists of plants grown primarily to keep the land covered, especially during the off-season or between cash crops. In temperate regions like most of Europe and North America, a cover crop sown immediately after the main crop harvest in fall is considered a winter cover crop. It will grow in the fall, either subjected to frostkill or go into relative dormancy ...

Two experiments were conducted in north-central Florida to examine the effects of various winter cover crops on plant-parasitic nematode populations through time. In the first experiment, six winter cover crops were rotated with summer corn (Zea mays), arranged in a randomized complete block design. The cover crops evaluated were wheat (Triticum aestivum), rye (Secale cereale), oat (Avena sativ...