Joe Lauer Extension Corn Agronomist
Department of Agronomy
UW-Madison College of Agricultural and Life Sciences
3:00 – Total Time
0:18 – Corn crop progress so far
1:02 – Roots searching for nutrients
2:33 – If you’re comfortable, corn is comfortable
2:43 – Good corn crop likely
2:50 – Lead out
Sevie Kenyon: Joe, how’s the corn crop look so far this year?
Joe Lauer: Most of the reports coming in are actually pretty good for most of the state, but when you get to the eastern and northeastern side of the state, there’s quite a bit of variability primarily due to late planting. And the corn crop is just trying to find the nitrogen, that fertilizer that the farmers put on. So you see a lot of uneven yellow corn that’s out there. And even in some of the better areas of the state, Dane County, Columbia County, you see a lot of yellowing as well too. So all in all it’s quite variable, but in general most of the acres I think are in pretty good shape.
Sevie Kenyon: Joe can you describe that phenomenon of the corn not being able to get the nutrients it needs?
Joe Lauer: A corn plant basically has a root system that goes thee feet to the side of it, and then about five to seven feet down in the ground. So that’s the volume that the root system can take nutrients up with. Most cornfields are planted in thirty-inch rows so those roots are going past the neighboring plants in the row. And it’s occupying a fairly large area of soil. When you apply nitrogen fertilizer, that nitrogen fertilizer, often times moves with the water itself. Though, when we get these hard rains or you get ponding or water accumulating in a field, that nitrogen moving with the waterfront, can move that nitrogen out of the root zone of that corn plant for a while. Eventually the corn plant can catch up and find that nitrogen in the profile, because again that’ll grow five to seven feet down and then once it does, the crop will green up again. And so a lot of these yellow uneven parts of the field that we see out there have been just areas where the nitrogen has moved out of the current rooting profile of the corn plant. But with time, eventually that corn plant will find the nitrogen and start to take it up and use it, and you’ll notice it and can tell by the fact that the plants green up and start to even up a little bit as the season progresses.
Sevie Kenyon: And Joe what would you say the crop needs for the rest of the season?
Joe Lauer: Really what’s comfortable for you and I is also going to be comfortable for the corn crop, and ideally we like to get that one inch of rain a week.
Sevie Kenyon: What kind of prognosis do you have for yields and so forth?
Joe Lauer: I think right now we’re set up pretty well for much of the state, except for maybe that northeastern part.
Sevie Kenyon: We’ve been visiting with Joe Lauer, Department of Agronomy, University of Wisconsin Extension and the College of Agricultural and Life Sciences, Madison, Wisconsin, and I am Sevie Kenyon.