AGRONOMIC CONSIDERATIONS OF ONE YEAR ROW CROP-SMALL GRAIN CROPPING SEQUENCES IN EASTERN NEBRASKA

WILLIAM MICHAEL SULLIVAN, University of Nebraska - Lincoln

Abstract

Experiments on sequential cropping systems were conducted at the University of Nebraska Field Research Laboratory, Mead, Nebraska on a Sharpsburg silty clay loam (fine, montmorillonitic, mesic, Typic Agriudol) to evaluate the production of various row crop-small grain sequences that might be used in eastern Nebraska. Three maturity classes of corn, sorghum and soybeans were grown under irrigated and nonirrigated conditions. The production and quality of grain produced by different row crops was determined. Winter wheat was planted immediately after row crop harvest. Oats were planted the spring following row crop harvest. Small grain seedbed preparation was accomplished by plowing and/or discing the row crop residue to prepare an adequate seedbed while maintaining a residue cover. The effects of previous row crop on the small grain seeding operation, growth and production were determined. Irrigated row crops produced larger amounts of grain than nonirrigated row crops. Variation about the mean was greater with irrigated crops as production was at a higher level than nonirrigated crops. Corn yield increased more with irrigation than sorghum and soybean yields. Row crop maturity class was related to grain production only in corn where grain yield was greater with later hybrids. Early season row crop cultivars tended to produce grain with lower test weights than full season cultivars. Row crop residue did not affect the small grain seeding operation unless soil surface cover exceeded forty-five percent which occurred only following corn and sorghum and substantially slowed seeding operations. Previous row crop affected wheat stand density only when the row crops were not irrigated. Wheat stands following nonirrigated soybeans contained 15 to 20% more seedling plants than wheat after corn or sorghum. Visual vigor ratings based on ground cover and plant height of oats following nonirrigated crops, and wheat after irrigated and nonirrigated row corps, were not affected by previous row crop. Oats were more vigorous when preceded by irrigated soybeans compared with oats following irrigated corn or sorghum. Oats following soybeans had superior vigor ratings and high early dry matter production. Wheat dry matter production at harvest was highest when preceded by irrigated corn. No differences in wheat dry matter production were detected when wheat was preceded by nonirrigated row crops. Total nitrogen in the herbage and percent IVDMD of small grains was not influenced by preceding row crop. As small grains matured IVDMD declined. Winter wheat was killed by low temperatures during the 1978-79 winter. Spring oat production and grain test weight were not affected by previous row crop. Moisture or temperature stress on small grains was not encountered in 1979. Grain yields averaged 21.9 q/ha and weighed 38.7 kg/hl. Moisture and temperature stress was severe during the period of active growth of the small grains in 1980. Wheat and oats following irrigated corn and sorghum had greater yield reductions than small grains following irrigated soybeans. Wheat produced 35.0 q/hl of grain weighing 78 kg/hl while oats produced 21.6 q/ha of grain that weighed 41.0 kg/hl after irrigated soybeans. Wheat and oat production after irrigated soybeans was 20 and 100% higher than wheat and oat yields after irrigated corn or sorghum. Non-irrigated 1979 row crops had no effect on subsequent small grains in 1980.

Subject Area

Agronomy

Recommended Citation

SULLIVAN, WILLIAM MICHAEL, "AGRONOMIC CONSIDERATIONS OF ONE YEAR ROW CROP-SMALL GRAIN CROPPING SEQUENCES IN EASTERN NEBRASKA" (1981). ETD collection for University of Nebraska-Lincoln. AAI8124523.
https://digitalcommons.unl.edu/dissertations/AAI8124523

COinS