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I just brought in some cow manure that has a lot of flies milling around in it. I think I identified them as the adult seedcorn maggot. Does anyone know how much trouble I might be in? Can they be controlled, or will they most likely not resurface in the spring with a fall application of Bayer complete insect killer to the soil?
Thanks for any input.

10/30/2009 12:07:54 PM

Western PA

Tony, now that I read your post, you have me thinking. I got a load of cow manure friday after work, and I noticed alot of flys that looked a little different to me but never considered that they could be harmful. They had longer wings than the common house fly, but I thought that they had the color of a fruit fly, like a light orange but I really didn't pay attention. Damn, I hope some one chimes in about this.
Would it hurt to add some grubex or something now ?

10/31/2009 6:47:36 PM

Ctpumpkin@optonline.net

Fresh manure should sit for an entire year. Spring applied Imidacloprid hasn't been effective against CSM around here.

Where are you located?

10/31/2009 9:27:20 PM

I'm in ohio and knew better that putting down fresh stuff, but I had access to a load and couldn't help myself. I only put down a small amount, maybe enough to only lightly cover the soil. Should I let it sit on top or till in?

11/1/2009 4:31:33 AM

Foley, Minnesota

Till the manure in. Seed corn maggots are attracted to manure, residue and rotting organic matter. Seed applied imidacloprid will be more effective than soil or plant applied treatments. Seed corn maggots attack the seedling early in the spring.

11/5/2009 12:19:50 PM

CSM are attracked to the OM in the manure, cow, horse, or a green manure cover crop makes no difference as Weed Nerd states. Thier life span and cycles are entirely soil temp dependent. Google will provide more info for those that desire.

11/5/2009 12:47:15 PM

Trumbull, CT 06611, USA

I have had many problems with corn seed maggots. That is what the flies are. You will most likely have them in the spring. 2 things that seem to work are merit and soil heating cables around the plant. The maggots like wet / cooler soil and feed on the organic matter. As long as the soil temps are kept over 70 in early spring (use heating cables), they will move somewhere else or hatch quickly.

Ray

11/5/2009 1:29:30 PM

Ctpumpkin@optonline.net

Ray is spot on with his findings. Another practice (where heat cables aren't practical) is SOLARIZING by laying cheap 1.5 mil CLEAR plastic on the planting area late winter. The warm soil will benefit the plant & cause weed seeds to germinate.

Imidacloprid treated seeds is an option. I have always treated our seedlings with Merit & have never suffered CSM. Then again we've gotten lucky and found ancient horse manure so between the two....no CSM.

11/5/2009 8:10:03 PM

Ham Lake, Minnesota

Turn on the heating cables two weeks before you plant. Put a little greenhouse tent over the area sealed to the ground. It will be like a bag of popcorn; you'll get a surge of flies and after a few days just a few more last minute ones, then they all drop dead and you're ready to plant.

11/5/2009 9:06:20 PM

Thanks for your responses.

11/6/2009 8:40:50 AM