Forage silage options sought after drought
Silage worries have had producers asking a bunch of questions this spring.
Brent Bean, Texas AgriLife Extension Service agronomist, Amarillo, has received many calls from beef and dairy producers and others who found themselves lacking good roughage sources last year for their cattle because of the drought.
• Producers are looking for forage options after the long drought.
• Sorghum forage doesn’t yield like corn, but it needs less water.
• Variety selection is important when growing sorghum forage.
“Most of the industry relies on corn silage, which did not do well last year during our extreme drought and high temperatures,” Bean says. “The industry is now looking for an alternative crop that uses less water and can tolerate high temperatures.”
As a result, Bean says, many are looking at forage sorghum. Although forage sorghum may not yield as much as corn under full irrigation, it requires about 30% less water than corn and is more heat-tolerant.
Bean has conducted forage sorghum trials in the Panhandle for many years and has summarized results from the last four years. Those results are at amarillo.tamu.edu under the agronomy program tab.
While the primary interest this year appears to be quantity, producers certainly should not ignore quality, especially silage going to dairy operations.
Bean notes he has included in his summary of varieties some indicators of quality, such as digestibility, and estimated pounds of milk produced per ton of forage.
The varieties in Bean’s trials were planted in late May on 30-inch rows at a seeding rate of 100,000 seeds per acre. Harvest started on early-maturing varieties in late August and continued through mid-October on late-maturing varieties.
All forage silage yields are reported at 65% moisture, he says. The varieties that consistently yielded above the test mean, had low lodging scores and were not photoperiod-sensitive included AS781, SS405, 849 F, 9500, FS-5, Millennium BMR, BMR Gold X and HiKane II. Two others, Silo 700D and HP 95 BMR, finished above the test mean in two of the four years tested.
The average yield over four years was 20.5 tons per acre, with a range from 18.4 to 26.8 tons per acre, Bean reports. Eighteen varieties consistently yielded above the annual test at least two-thirds of the time.
Lodging is an important issue in sorghum silage production and can vary greatly from year to year, depending on the conditions, he says. Of the 18 best-yielding varieties tested, six had lodging scores of greater than 15%. If these varieties are planted, producers should plant at a lower seeding rate and make sure the field is not overfertilized with nitrogen to help prevent lodging.
“In addition, it is important that these varieties are harvested as soon as they reach the proper moisture, which is usually at soft dough stage,” Bean says. “Delaying harvest past the optimum time can lead to increased lodging.”
Ledbetter is with Texas A&M Ag Communications, Amarillo.
This article published in the May, 2012 edition of THE FARMER-STOCKMAN.