HARTLY, Del. — Farmers growing corn for silage should pay close attention to what varieties of corn they grow.
A sexy stand of luscious and leafy corn may not be the best variety to choose, according to Ev Thomas of Oak Point Agronomics in Hammond, N.Y. That was one of the messages of the annual University of Delaware Delmarva Dairy Day held Thursday, Feb. 14, in Hartly. Thomas was one of several featured speakers during the day.
Thomas said the focus of most seed companies is on grain. With some 92 to 93 percent of corn used as grain and not silage, research on better varieties for silage has not been the highest priority.
Thomas said that many leafy hybrids look good, but may not be the best choice for farmers growing corn for silage. He said farmers may want to consider BMR (Brown Midrib Hybrids) varieties of corn for silage.
BMR corn is a naturally occurring mutation that was found in 1924. The corn stalk has less lignin, which means it can be significantly more digestible when used as silage than more traditional corn varieties.
BMR, however, is far from a silver bullet for farmers. Thomas said BMR corn produces a 5 to 10 percent lower yield, has a higher seed cost and is not very drought tolerant. It also should be grown and stored separately. The decreased yield difference is made more significant in drought years, such as those Delmarva farmers have experienced recently.
“BMR isn’t for all dairy farms,” he said.
Thomas said the best response from BMR corn is from high-producing cows milking over 100 pounds. He also said it is great feed for transition and fresh cows.
There is relatively little benefit from BMR corn when fed to nonmilking heifers or cows producing less than 60 to 70 pounds, he said.
“It looks different. It grows different. It tests different. Fiber fragility is different. It feeds different. Some say it even tastes different,” Thomas said.
He said that there are also potential standability problems because of the lower lignin content. California farmers have had some problems when the corn grew very tall, but Thomas said he has grown the corn for eight years with very few problems.
Thomas said some conventional hybrids have good digestibility. Some do not. Conventional leafy hybrids also look good in the field.
Thomas drew laughter when he said that we all like our crops to look good and that leafy hybrids produce more attractive stands of corn. We all like to hear “Joe’s corn looks pretty good this year,” he said.
“Leafies have sex appeal and sex sells, whether it’s in the movie theater or the corn field,” he said.
Thomas told farmers that leafy varieties are a good option if they have good digestibility. Farmers should not assume that the newest hybrids have better digestibility, but should rely on trial data, he said.
BMR is not for all cows on a farm. “But BMR makes cows milk,” he said.