I retired from Miner Institute in 2008 but have yet to discover what retirement is all about. I’ve often said “better to wear out than to rust out,” and this hasn’t proven to be a problem, since almost every morning I spend an hour or so online and am often asked – by farmers, extension educators and other agricultural professionals – to help diagnose and suggest solutions for crop problems. I also spend a modest amount of time on farms, which is sometimes the only way to get to the bottom of a problem. While the occasional problem may seem unique, most are recurring – not on the same farm (hopefully!), but within the Northeast. Here are three we’ve been dealing with in recent months.
This is one of the most frustrating and challenging dairy feed problems, both in dealing with the impact of high-mycotoxin silages and in trying to figure out what happened in an attempt to prevent future occurrences. Some years ago, I participated in an ambitious survey of dairy farms with known mycotoxin problems in New York, Vermont and Wisconsin. We obtained completed, detailed questionnaires on these farms, including a survey of the closest dairy farm of similar size/style of operation that didn’t have a mycotoxin problem. The University of Wisconsin did analyses on the problem farms to confirm that they actually had a mycotoxin problem.
The objective was to find factors that might predispose a farm to a mycotoxin problem, either in the field or in the silo. We tabulated the results of the completed surveys and found … nothing. There wasn’t any factor we could single out that would separate the two groups of farms. Diagnosing a mycotoxin problem isn’t difficult, but predicting one sure is! We’ve seen times where all sorts of field and harvest issues occurred, but there weren’t any problems. In other cases, a mycotoxin problem occurred without any detectable cause or warning.
In spite of our difficulties in predicting an occurrence, here are two suggestions for reducing the chances of mycotoxin problems. First: If possible, harvest corn for silage before it’s killed by frost. If frost does kill the plant, then harvest the corn as soon as possible – that means days, not weeks.
A serious case of mycotoxins I encountered this past summer, accompanied by reduced milk production, reproductive problems and digestive upsets, was in corn silage that had been killed by frost and then allowed to remain in the field for a week or more before it was harvested. Molds begin to develop soon after corn is dead, and some of these molds may produce mycotoxins. Mycotoxin problems are detected in the silage, but they begin in the field.
Second: Monitor your crop for foliar diseases, including northern corn leaf blight. Foliar diseases don’t produce mycotoxins, but they can kill the plant prematurely and create favorable conditions for molds and mycotoxins. If you have leaf blights, make sure you harvest these fields as soon as they’re at the recommended whole plant dry matter (DM) of 32 to 35 percent. I’d start at 32 percent DM if there are a lot of diseased and dying leaves. Also, hybrids differ in resistance to northern corn leaf blight, so you might consider ordering hybrids with a higher level of resistance for next year.
Winter damage to forage grasses
In a 1977 article, I extolled the virtues of reed canarygrass. Low-alkaloid varieties of this species had become available that resulted in improved animal performance, and well-managed canarygrass would really put out the tonnage. Eventually, as we learned more about the forage quality of reed canarygrass compared to other grass species, tall fescue seemed like a better choice. Tall fescue was competitive for yield in Cornell University variety trials and had a distinct quality advantage.
We tried to practice what we preached and stopped using reed canarygrass in alfalfa-grass seedings at Miner Institute, switching to one of the many varieties of endophyte-free tall fescue that were entering the marketplace. At about the same time, I started recommending this species to farmers.
All went well until the winter of 2013-2014, when the combination of an ice storm and long stretches of subzero weather, including lows approaching minus 30 degrees Fahrenheit in northern New York, severely damaged both alfalfa and tall fescue in some alfalfa-grass stands. These conditions also damaged orchardgrass, but didn’t seem to have much impact on reed canarygrass, which seems impervious to cold or wet. (In fact, the only malady we’ve ever found to damage canarygrass is an armyworm infestation. Armyworms seem to prefer this grass over all others.) I’m of the opinion that the winter damage affecting tall fescue is a one-off, a perfect storm of ice and frigid conditions that’s unlikely to occur again any time soon.
Hitting a moving target
Agronomists who work with dairy farmers have to remember that the No. 1 objective of forage production is to provide the quality and quantity of crops needed for economical milk production. These requirements differ from farm to farm depending on production level and soil resources.
For instance, the hay crop quality needed to produce 18,000 pounds of milk per cow is much different than that needed to produce 28,000 pounds. As herd size increases, the tendency is to increase the acreage of corn harvested for silage more than the acreage used for hay crops. This will, in many cases, necessitate a change in the crop rotation, which in turn may change weed and insect management. I get more questions from farmers who are in the process of making some of these changes than those who have a relatively constant acreage of crop species and are reasonably satisfied with their forage quality.