By Brian Hefty
Goss’s Wilt is a bacterial disease, so fungicides (both seed treatment and foliar) won’t control it. Goss’s Wilt can overwinter even in the Northern U.S., so winterkill won’t control it. Goss’s Wilt seems to be more abundant in continuous corn, in susceptible hybrids, in reduced-till or no-till, in weedy fields, and if plants get damaged by insects, weather, or in any other way. I have personally never seen more Goss’s Wilt than I did this year, and I believe it is now one of the biggest yield-robbers in corn. If you haven’t seen Goss’s Wilt on your farm, yet, you are either lucky or you may not have been looking hard enough. When you’ve got this disease, it may only take a few bushels, but in many cases we’ve seen it knock yields down 20 to 80 bushels per acre!
Hopefully I have now sufficiently convinced you that Goss’s Wilt is something you don’t want. While we currently have no way to control it on the farm, there are many things you can do to better manage it. Here are my best suggestions for your farm:
- Learn more about Goss’s Wilt and put that knowledge to use. Don’t think this can’t affect you based on past history. That’s what I said on our farm, too, before it took a bunch of my yield.
- Don’t plant corn. This disease doesn’t affect soybeans, sunflowers, alfalfa, or other broadleaf crops. To this point, we also haven’t seen any Goss’s Wilt in small grains.
- Don’t plant continuous corn. Goss’s Wilt has been far more prevalent following corn vs. following any other crop since it commonly survives the winter on corn residue.
- OK. You don’t like choice #2 or choice #3. I don’t either. If you insist on planting corn, like we will on our farm, you will definitely want to pick the right hybrids. Some varieties are very susceptible. Some varieties are very tolerant. Here’s the trick…some varieties were produced in areas this year with low Goss’s Wilt pressure, so we’re slightly concerned a company may feel a hybrid has good tolerance even without thorough in-field testing. Just make sure you know what you’re getting. Talk to several agronomists, and preferably corn breeders, so you have a better idea whether or not you’re actually getting the best products for Goss’s Wilt.
- Keep your fields weed free. Weeds such as barnyardgrass, green foxtail, and shattercane are known hosts for Goss’s Wilt.
- Use tillage to bury infected residue. Personally, I hate this step, as increasing tillage costs money and it can lead to increased erosion and decreased organic matter and cation exchange capacity levels in soil. However, if you’ve got a major problem, burying residue containing Goss’s Wilt can help.