Western Kansas Field Station Weather Report: 2022 Growing Season

Summary of 2022 weather for research conducted at the research locations included in the 2023 Western Kansas Agricultural Research report

Land application of animal waste on irrigated fields

Presented at the 2007 Central Plains irrigation conference on February 27-28 in Kearney, Nebraska.Animal wastes are routinely applied to cropland to recycle nutrients, build soil quality, and increase crop productivity. This study evaluates established best management practices for land application of animal wastes on irrigated corn. Swine (effluent water from a lagoon) and cattle (solid manure from a beef feedlot) wastes have been applied annually since 1999 at rates to meet estimated corn P or N requirements along with a rate double the N requirement (2xN). Other treatments were N fertilizer (60, 120, and 180 lb N/a) and an untreated control. Corn yields were increased by application of animal wastes and N fertilizer. Over-application of cattle manure has not had a negative effect on corn yield. For swine effluent, over-application has not reduced corn yields except for 2004, when the effluent had much greater salt concentration than in previous years, which caused reduced germination and poor early growth. All animal waste and N fertilizer treatments increased soil solution NO3-N concentration (5-ft depth) compared with the untreated control. Application of animal wastes on a N requirement basis resulted in similar NO3-N concentrations as fertilizer N applied at 180 lb/a (approximate recommended rate). The 2xN application caused NO3- N concentrations to about double for both swine and cattle wastes. Application of swine effluent based on P requirement produced similar NO3-N concentrations as the 2xN rate because of the relatively low P content in the effluent

Wheat and Grain Sorghum Sequencing for Three Crops in Four-Year Rotations

In 1996, an effort began to quantify soil water storage, crop water use, and crop productivity on dryland systems in western Kansas. Research on 4-year crop rotations with wheat and grain sorghum was initiated at the Southwest Research-Extension Center near Tribune, KS. Rotations were wheatwheat- sorghum-fallow (WWSF), wheat-sorghum-sorghum-fallow (WSSF), and continuous wheat (WW). Soil water at wheat planting averaged about 9.1 in. following sorghum, which is about 3.8 in. more than the average for the second wheat crop in a WWSF rotation. Soil water at sorghum planting was only about 1.5 in. less for the second sorghum crop compared with sorghum following wheat. Sorghum grain yield in 2022 was near average for first crop sorghum after wheat, above average for recrop sorghum, and below average for sorghum after recrop wheat. Wheat yields in 2022 were near zero due to hail. Wheat yields, when averaged across years, have been 2 bu/a greater following two sorghum crops than following one sorghum crop. Average sorghum yields were the same following one or two wheat crops. Yield of the second sorghum crop in a WSSF rotation averages ~66% of the yield of the first sorghum crop

Tillage Intensity in a Long-Term Wheat-Sorghum-Fallow Rotation

This study was initiated in 1991 at the Kansas State University Southwest Research-Extension Center near Tribune, KS. The purpose of the study was to identify the effects of tillage intensity on precipitation capture, soil water storage, and grain yield in a wheat-sorghum-fallow rotation. Grain yields of wheat and grain sorghum increased with decreased tillage intensity in a wheat-sorghumfallow (WSF) rotation. In 2022, available soil water at sorghum planting was greater for no-tillage (NT) than reduced tillage (RT), which was greater than conventional tillage (CT). For wheat there was a similar pattern as sorghum, with available soil water at wheat planting being in the order of NT\u3eRT\u3eCT. Averaged across the most recent 22 years of the study, available soil water at wheat planting was 0.60 inch greater for NT than RT and approximately 1.7 inches greater than CT. Average available soil water at sorghum planting was greater in the order RT=NT\u3eCT averaging 7.9 inches for RT and NT and 5.9 inches for CT. Averaged across the past 22 years, NT wheat yields were 6 bu/a greater than RT and 10 bu/a greater than CT. Averaged across the past 22 years, sorghum yields with long-term NT have been 57% greater than with RT (82 vs. 52 bu/a)