Department of Crop and Soil Sciences

Extension Series No. E01-1

January, 2001

  NEW YORK CORN SILAGE HYBRID TESTS - 2000

We initiated the annual testing of corn silage hybrids at four locations in New York in 2000. We evaluated 95 to 115-day hybrids in relative maturity (RM) at Aurora and Batavia, experimental sites that average about 24000 growing degree days (GDD, 86-50^o system) from May through September. We evaluated 80 to 100 day hybrids in RM at Canton and Chazy, experimental sites that average about 2000 GDD from May through September.

Both sites were exceptionally wet from April through June. Although the Chazy site was planted in mid-May, final stands were very erratic so only portions of each plot were harvested. The Canton site was planted in mid-June so final stands were much better. Nevertheless, harvest densities ranged from 25000 to 31000 plants/acre, which was more variation than we wished. July was also exceptionally cold at both sites so hybrids did not attain the � milk line stage at Canton.

Similar to the Aurora and Batavia experiments, site x hybrid interactions did not exist for silage yield, quality characteristics, or calculated milk yield. Once again, we averaged all data across sites so each value is the mean of eight observations (Tables 1 to 3). Unlike the Aurora and Batavia experiments, most hybrids had statistically similar silage yield, quality characteristics, and calculated milk yield. The lack of differences among hybrids can be attributed in part to less precision, especially for silage yield, associated with differences in harvest populations among hybrids at both sites and lack of hybrid maturity at Canton.

In the 95 to 99 day RM range, nine of the 10 hybrids had statistically similar calculated milk yield (Table 1). The hybrid T29400 had the numerically highest silage yield, GS998 had the numerically highest IVTD and NDF digestibility, and 38K06 had the numerically lowest NDF. Despite the fact that most hybrids in this RM range had only attained the early denting stage, most hybrids had average IVTD and NDF. The NDF digestibility for most hybrids, except for GS998, averaged less than 51%.

In the 90 to 95 day RM range, eight of the nine hybrids had statistically similar calculated milk yield (Table 2). HLS034 had the numerically highest silage yield, DKC42-22 had the numerically highest IVTD and the lowest NDF, and NX3018 and TMF2404 had the numerically highest NDF digestibility. As with the 95 to 99 day hybrids, most hybrids had average IVTD and NDF but low NDF digestibility.

In the 85 to 89 day RM range, all hybrids had statistically similar calculated milk yield (Table 3). The hybrids HLS113 and HL 2240 had the numerically highest silage yield, which contributed to their numerically highest milk yield. The hybrid HLS012 had the numerically highest IVTD and lowest NDF. Although the 85 to 89 day hybrids were further along in maturity at Canton compared with the 95 to 99 day hybrids, the IVTD and NDF were similar among the two hybrid maturity ranges.

The 2000 growing season in New York was very challenging because of excessively wet conditions in the spring and the excessively cool conditions in July. The Aurora and Batavia sites were planted in a timely manner and most hybrids had excellent yields with high IVTD. Furthermore, the overall precision of these experiments were excellent as indicated by the low LSD values. The Canton and Chazy sites, however, had delayed planting or stand establishment problems, which contributed to somewhat low yields and less overall precision, especially at Chazy. Consequently, we could not detect differences among hybrids for most parameters at the Canton and Chazy sites.

NDFd = Fiber digestibility.

MYIELD95 = Milk Yield using Wisconsin�s MILK95 program.

MYIELD00 = Milk Yield using Wisconsin�s MILK2000 progam.