Effects of grazing corn plant residue on beef cattle performance, residue characteristics, and subsequent crop yield

Our objective was to evaluate the effects of grazing method on beef cattle performance, residue characteristics, and subsequent corn grain yields. This was a 3-yr study in which strip-grazing (SG), continuous grazing (CG), and ungrazed control (CT) treatments were arranged in a randomized complete block design with 3 replications per year on a continuous corn production system in central Illinois. Strip-grazed plots were divided into subplots (1, 2, 3) in which cattle back-grazed. Thirty-six spring-calving, multiparous, Angus cows were used in the first and second year of the study and 42 winter-calving Angus heifers were used in the third year. Cattle grazed for 42 d each year following corn harvest. Cattle in SG plots were 9.8 kg heavier (P = 0.05) postgrazing compared with those on CG plots but did not differ (P = 0.77) in final BCS, indicating adequate performance was maintained regardless of treatment. The SG and CG plots had increased ADF (P = 0.03) and decreased CP (P < 0.01) after grazing compared with CT. In year 2 postgrazing, SG and CG had decreased (P < 0.01) total residue availability, leaves and husks, and cobs compared with CT, suggesting more digestible, nutrient-dense components were selected during grazing. No differences (P = 0.16) were detected for corn yield among grazing treatments. However, yield was different (P = 0.05) among strips. Strip 1 had lower yields than strip 2, which may have been due to increased cattle trafficking in this area. Both grazing methods resulted in acceptable performance. Grazing corn residue did not affect subsequent crop yields; however, strip differences in yield within strip-grazed paddocks warrant further investigation.