News

Dry start delayed tar spot, but look out now

A plant disease expert says the very dry start of the growing season helped delay the first signs of tar spot in corn.  Damon Smith with the University of Wisconsin tells Brownfield tar spot has now been reported in a few Wisconsin counties, and it’s likely just the beginning. “Now, we’re getting some rainy periods and we do know some of our most recent research and modeling efforts have shown that these wet-dry cycles tend to push it a bit harder, so I am expecting it to kind of ramp up.”

Smith says the late start for tar spot should lessen the risk of significant disease-related yield losses. “We might see a little bit of yield reduction, just depending on how fast it moves and how susceptible a hybrid is so I’m maybe not expecting quite as significant an issue as we’ve had the last couple of seasons.”

And, if corn shows tar spot in this unusually dry year, “What you want to do is actually take a really hard look at the variety or hybrid because what that tells me is, you know, in conditions like this, if you’re seeing disease, then that tells us that on the variety side, that particular variety is probably very susceptible.”

So far, Smith says farmers are reporting northern corn leaf blight, but he hasn’t had any reports of Frog Eye Leaf Spot in soybeans, and there are fewer reports of soybean white mold this year.