Corn Silage

Experimental Procedures 

AgResearch and Education Center Tests: Six corn hybrids were evaluated for silage yield and quality in 2022. The tests were conducted at the Highland Rim (Springfield), Middle Tennessee (Spring Hill), Plateau (Crossville), East Tennessee (Knoxville), and Northeast Tennessee (Greeneville) AgResearch and Education Centers. The plots at all locations consisted of two rows, planted 30 inches apart, 30 feet in length. Entries were arranged in a randomized complete block design with three replications. Yields were adjusted to both dry weight and 65% moisture. Plots were planted at 36,000 seeds/ac with a population goal of 34,000 plants/ac. The resulting plant populations, as well as the planting and harvesting dates, are given in Table 1. Plots were harvested using commercial silage harvesters. A sub-sample of approximately 3 lbs was taken from each plot for analysis. Fresh weight and dried weight were recorded on each sample for determination of moisture at harvest. Dried samples were then ground and analyzed for nutritive content. Silage quality analyses were provided by the UT Beef and Forage Center using a Foss DS2500F (Foss North America, Eden Prairie, MN) instrument with the 2021 Unfermented Corn Silage calibration provided by the NIRS Forage and Feed Consortium (Berea, KY). Predictions for milk production per ton and milk production per acre were calculated using the University of Wisconsin Milk2006 program. 

Growing Season: Corn silage official variety trials were planted between late-April and late-May at the University of Tennessee AgResearch and Education Center (REC) locations. Early season rains delayed corn planting throughout the state in April. The weather remained mixed throughout planting, allowing for a large amount of planting to take place in short bursts in mid-May. Statewide corn planting caught up to the five-year average by mid-May, with 84 percent of corn planted in Tennessee. Drought conditions prevailed across the state from mid-June to mid-July, stressing young corn during critical growing periods. Rains in the end of July and early August came too late to aid in corn development. By late August, 29 percent of the crop was rated good to excellent. The Greeneville location averaged 36% moisture at harvest, which is well below the recommended moisture range for harvesting corn silage. Therefore, this location was dropped from the analysis. The Spring Hill location had very low yield and poor quality due to the unfavorable weather conditions this year. This location was kept in the analysis as it is representative of conditions observed across the state this year on non-irrigated acres. 

Interpretation of Data: 

The tables on the following pages have been prepared with the entries listed in order of yield performance, the highest-yielding entry being listed first. Mean separation was performed using the Fisher’s Protected LSD (Least Significant Difference) test. The mean trait value of any two entries being compared must differ by at least the LSD amount shown to be considered different at the 5% level of probability of significance. To simplify interpretation, Mean Separation Letters have been listed next to each entry for traits analyzed across locations. Hybrids that have any letter in common are not significantly different in yield at the 5% level of probability based on the LSD test. Hybrids with performance not significantly different from the top performing hybrid will have an “A” included in the list of mean separation letters next to that entry.