| Description: |
The objective of this project was to evaluate the effect of interseeding cereal rye (Secale cereale) into corn (Zea mays) for use as grazed forage after corn grain harvest on corn grain yield and additional grazing day· ha-1. In a 4-year study, corn was planted (64,246 plants· ha-1) in spring on two, 4.8-ha fields in central Pennsylvania. Cereal rye was interseeded (135 kg· ha-1) into the corn at the V4-V6 stage. Corn was harvested as grain in November and each field was divided into six, 0.8-ha paddocks and randomly assigned to either grazed (GRAZ) or ungrazed (NG) treatments. Beef cattle frontal-grazed three of the paddocks (four cows· paddock-1) in each field approximately four to five weeks after corn grain harvest and, if re-growth allowed, again in early spring before subsequent corn planting. Corn grain, corn fodder (after grain harvest), and cereal rye yields were monitored each fall. Cereal rye growth was also monitored in early spring. Statistical analyses on corn grain yield and forage biomass were conducted using the MIXED procedure in SAS 9.4 (SAS Institute, Cary, NC, USA). Least square means were separated using Fisher’s least significant difference test (α = 0.05). There were no site by treatment interactions, therefore means are presented as an average across both sites (Table 1). Corn grain, corn stover, and cereal rye yields were affected by year. Corn grain yields did not decrease as a result of grazing, or of repeated plantings of corn, ranging from 9,516-10,088 kg· ha-1 across GRAZ and NG paddocks except in 2019 (dry year) when corn grain yields averaged 6,053 kg· ha-1 across both GRAZ and NG treatments. Spring grazing only occurred in one year (2021) due to insufficient cereal rye growth in the other years. On average, the cereal rye (plus the corn stover) provided enough forage for an additional 115-130 grazing days· ha-1 in the fall. Results of this study showed that when corn is harvested too late in the year to establish a cover crop, interseeding annual forages into growing ... |