29 replies to this topic

[Cattech]

Think I ruined Father's Day for Dad, I took a four wheeler ride around the farm today and ended up breaking some bad news.
Dad sprayed some left-over Accent Gold and Prowl in some areas, atrazine and oil in a few other areas, all on Liberty Ready corn, & things don't look good. Corn looks like a massive hail storm came through in all the lower ground. Ends of leaves appear shredded off, holes through the leaves closer to the stems, everything curled to the ground. Even worse - the grass is still green. Corn up on higher dry ground seems OK, so I don't think it was hail. Just wondering if conventional corn herbicides and the GMO corn can have adverse reactions.

[BLUEPOWER]

Atrazine damage will leave white spots on the corn, but Ive never seen it damage leaves like you are talking about. As far as spraying conventianal chemical on GMO crops, that what I have 90% of my customers doing with their corn now. They like the traited corn for the insect control and plant health, but are wanting to get away from spraying round up every year on the same farm. Could you post a pic of the hurt corn?

[Cattech]

Atrazine damage will leave white spots on the corn, but Ive never seen it damage leaves like you are talking about. As far as spraying conventianal chemical on GMO crops, that what I have 90% of my customers doing with their corn now. They like the traited corn for the insect control and plant health, but are wanting to get away from spraying round up every year on the same farm. Could you post a pic of the hurt corn?

Sorry, I didn't think to get any pics and it's 50 miles from my house. I didn't see any white spotting, there were holes through some of the leaves, 1/8" to 1/4" around that looked very similar to the holes in the leaves of the weeds that were still there. Most of the corn's leaves had the ends burnt off, like it was torn off, but the edges had the same look as around the edges of the holes. Also, the plants had a slightly blackened look to them. It seemed to be worse down in the lower areas, like it was run-off concentration damage. Over on one side of the farm, what probably was one of the first tanks he sprayed, the corn is looking quite healthy.

[hillskinefarms]

I'm no expert, but I'm quite sure conventional herbicides work fine on GMO corn. I've done it alot with no ill effects, as long as you use labled rates. Are you sure it's not insects? We have had cutworm problems here and armyworms are one county south of us.Maybe insect pressure and herb. stress both?
P.S.- I took a ride tonight myself and saw what happens when you clean the sprayer but don't flush the booms-the first pass in oats for about 30 feet I fried them and I mean FRIED!!!!

[Cattech]

I'm no expert, but I'm quite sure conventional herbicides work fine on GMO corn. I've done it alot with no ill effects, as long as you use labled rates. Are you sure it's not insects? We have had cutworm problems here and armyworms are one county south of us.Maybe insect pressure and herb. stress both?

We've never had an insect issue, at least this early in the season. I admit though, some of the damage really looked like that could be the issue, I'm at a loss to what could eat that much of the plants in early June here in MN.
I didn't think there were any problems with non-GMO herbicides on GMO corn, but just thought I'd ask around.
Another variable this year, is we put lime down last fall for the first time. The soil PH was pretty bad, I've heard that it takes a season for the lime to incorporate, possibly the unusual amounts of rain we've had could have washed soil and concentrated the lime levels?

[Birdman]

How much lime did you apply? I could be wrong but it takes a rediculous amount of lime to have negative affects on a crop. Especially where the PH was low to start with. In fact I'm not sure you could apply enough lime in one year to have such an effect.

I'm leaning toward just straight out hail damage, no idea why it's spotty but hail does some strange things. Only other thing I can imagine is maybe he picked up a box of the wrong herbicide but thats awefully strange damage, from what I gather, for herbicide damage. You didn't by any chance notice an over abundance of grasshoppers did you?

[Cattech]

How much lime did you apply? I could be wrong but it takes a rediculous amount of lime to have negative affects on a crop. Especially where the PH was low to start with. In fact I'm not sure you could apply enough lime in one year to have such an effect.

I'm leaning toward just straight out hail damage, no idea why it's spotty but hail does some strange things. Only other thing I can imagine is maybe he picked up a box of the wrong herbicide but thats awefully strange damage, from what I gather, for herbicide damage. You didn't by any chance notice an over abundance of grasshoppers did you?

Haven't seen any grasshoppers, I won't discount insects with the mild winter we had though. I won't discount hail either, just odd with the small holes in the leaves and the blackened plants. And as I said, the grasses he was trying to kill are still fine.
This is actually looking like more of a mystery than I first thought, I'll see if I can get some pics to post.

[Birdman]

Well, holes from insects are usually pretty clean, hail damage holes are generally more like splits in the leaves from what I recall. Complete mystery with the grass still being okay....
Wireworms will make corn look like it was shot with a shotgun but never seen the corn look blackish like from frost...

[PJB]

http://extension.ent...ue11/index.html
This website shows the damage different insects cause in corn. You could google images for ones that look similar to yours and might find some different pictures that match your damage. Paul

[hillskinefarms]

Cattech- are you any closer to solving this mystery? The more I think about it I wonder if you are seeing several symptoms at once. Just curious as to what you found out.