Chemical Attributes of Soils Subjected to No-Till Cropping with Rye Cover Crops
1991
Eckert, D. J.
Rye (Secale cereale L.) cover crops are often promoted to supply additional residue in no-till production situations; however, the effect of inclusion of rye on soil chemical properties is largely unknown. Soils were sampled, 20 cm deep, from four 4-yr studies in which no-till corn (Zea mays L.) and soybean (Glycine max L. Merr.) were grown continuously or in rotation on a Canfield silt loam (fine-loamy, mixed, mesic Aquic Fragiudalf) or in rotation only on a Hoytville silty clay (fine, illitic, mesic Mollic Ochraqualf), with and without a winter rye cover crop. Corn had been fertilized each spring with 224 kg N ha⁻¹ as either injected anhydrous ammonia or surface-broadcast urea-ammonium nitrate (UAN) solution. All plots sampled showed greater concentrations of organic C, exchangeable K, and Bray-1 extractable P in the surface 5-cm increment of soil than deeper in the sampled profile. Exchangeable Ca and Mg concentrations were often less at this depth than deeper in the profile, particularly when N was applied as surface-broadcast UAN solution. Soil pH was generally lowest in the zone of N application. Addition of the rye cover crop had little effect on the distribution of chemical attributes, other than increasing concentrations of exchangeable K near the soil surface in several comparisons. Salaries and research support provided by state and federal funds appropriated to the Ohio Agric. Res. and Development Ctr., Wooster, OH 44691. Journal Article 179-90.
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