Controlling Henbit, Purple Deadnettle to Prevent SCN

For the casual observer, those Indiana farm fields of purple might look kind of pretty, but farmers know that henbit and purple deadnettle are just weeds that need controlled. A mild winter allowed weeds to get a good head start this year.

“We’ve had these purple flowered weeds, henbit and purple deadnettle, for decades in this area and throughout the Corn Belt,” says Dr. Bill Johnson, Purdue professor of weed science. He’s a guest on the latest Purdue Crop Chat Podcast, available now at hoosieragtoday.com or wherever you listen to podcasts.

“The key thing to remember about these winter annual weeds is if we don’t get them controlled, they can go on and produce seed and obviously, produce a seed bank for future years. But also, in conditions where we have daytime air temps in the 60s and some wet soils, the soils will not dry out very rapidly either. They’ll kind of form a mat and they’ll prevent water from evaporating.”

Johnson warns that henbit and purple deadnettle can also serve as an alternative host to soybean cyst nematode.

“And so, when we have what appears to be the pattern that we’re in now with kind of a warm, extended spring, but a little on the wet side, if we’re not able to get the henbit and purple deadnettle controlled, we can allow more reproduction of SCN on those weeds in the springtime as well which can increase higher populations of those weeds in the long run.”

Johnson adds that, “if we’re in the pattern that we’re in now, where our daytime air temps are primarily highs in the 50s, lows in the 30s, I think we’re still okay to spray under those conditions. But expect the herbicides to work more slowly.”

Hear more from Johnson, Dan ‘Corn’ Quinn, ‘Soybean Shaun’ Casteel, and new Extension Weed Specialist Tommy Butts on the new Purdue Crop Chat Podcast below.

Purdue Crop Chat

Purdue Crop Chat Episode 73, 2024 Research Review

Purdue Crop Chat

Purdue Extension's Dan 'Corn' Quinn & 'Soybean Shaun' Casteel provide timely agronomic info on the Purdue Crop Chat Podcast! Joined by HAT's Eric Pfeiffer, Quinn & Casteel can't help but debate which is better- corn or soybeans? This podcast is presented by the Indiana Corn Marketing Council and Indiana Soybean Alliance.