# Webworm in Hay



## stilsonian (May 27, 2015)

We're having a bit of a problem with our perennial peanut bales accumulating some form of webworm on the perimeter bales (tops and sides of the bales that are exposed). We barn keep all of our hay and only have an issue with the perennial peanut bales. We sell most of our hay to clients that feed it directly or resell it, so appearance matters, and having a web and worm fecal matter on the side is a bit of a deal breaker. I'd love to be able to spray a preventative when stacking bales, or at the very least, a killing agent once the worms appear. My concern is that anything I spray might ruin the aroma of the bales or (worse yet) be harmful to the livestock (dairy goats and high end horses).

Anyone have any ideas? Anyone experience anything similar with alfalfa webworms?

We have no damage in the field, it's only once baled and only if stored with abundant access to airflow (bales stored in a shipping container are clean as the day they were baled).

Here's what we're dealing with.


----------



## Vol (Jul 5, 2009)

I would try alcohol and water 50/50 as a killing agent early on if I could not find a preventative. I think that would leave you with the least amount of undesirable residue.....and would dry quickly with no odor.

Regards, Mike


----------



## somedevildawg (Jun 20, 2011)

That's strange......Never seen that before, I'll do some asking around here.....I think we can assume they are airborne since they are not in the bales in the trailer?


----------



## stilsonian (May 27, 2015)

Yeah, they're definitely airborne. I'm thinking of it in the same class as a fall webworm, which are once generational per year for us and have eggs laid by moths.

I'll try the alky/water mix. Local guys suggest Malathion, but it has a pretty negative odor and I'm not sure I want it on livestock bound hay.


----------



## stilsonian (May 27, 2015)

Submitted a sample to the county ext office bound for UGA. Spoke at length with Will Hudson of the UGA Entomology Dept. this afternoon. We're confident a post-emergent application of a pyrethroid (we use Cyper-Ag) will be most effective. I have plenty of experience with this product and it's relatively odorless. I'll post more as I get more info.


----------



## somedevildawg (Jun 20, 2011)

stilsonian said:


> Submitted a sample to the county ext office bound for UGA. Spoke at length with Will Hudson of the UGA Entomology Dept. this afternoon. We're confident a post-emergent application of a pyrethroid (we use Cyper-Ag) will be most effective. I have plenty of experience with this product and it's relatively odorless. I'll post more as I get more info.


When you say "post emergent" do you mean "post baled"? Are you going to spray it on the baled product.....not that I see any problem with that as long as the required waiting period has elapsed. Just left me a bit confused.....easy to do. I haven't sprayed a pyrethroid before that didn't have an odor, they all stink like crap to me......but it dissipates relatively quickly


----------



## stilsonian (May 27, 2015)

somedevildawg said:


> When you say "post emergent" do you mean "post baled"? Are you going to spray it on the baled product.....not that I see any problem with that as long as the required waiting period has elapsed. Just left me a bit confused.....easy to do. I haven't sprayed a pyrethroid before that didn't have an odor, they all stink like crap to me......but it dissipates relatively quickly


Yes, as I mentioned, the issue is only on stored bales (there are no known pests (incl. nematodes) for actively growing perennial peanuts), so I'm looking for a solution to ultimately prevent the occurrence of the "webworms". However, a post-emergent (or reactive) solution is at least a solution, so I'm willing to try that as well. Cyper-Ag (cypermethrin - 30.6%) has a minimal odor when mixed in a spray solution (I just made some) as it requires such a small mix to be effective (as little as 3.75oz per acre when applied at 15 gal per acre). So, that's only 7.5mL per gallon via pump-up sprayer or 1.875mL per 32oz for a spray bottle.

I'm hoping it'll be effective at those rates (same rates I have great success with armyworms at in the field), but can nearly double the rate if necessary. Gonna try on a few bales, wait the required time, and feed to some livestock I can afford to lose (if there is such a thing).


----------

