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

Objective: Our objective was to evaluate the effects of grazing method on beef cattle performance, residue characteristics, and subsequent corn grain yields. Materials and Methods: 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. Results and Discussion: 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. Implications and Applications: 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.