Jan 8, 2012 – Getting To The Heart of The Problem

QUESTION:

I have an account with a dry goods area. The product coming in is full of meal moths, where you can actually see larva in the sealed products. Switching the vender is not an option. Is there a bug light that will work on these moths or some type of misting system?

ANSWER:

From your description I would have to say no to both suggestions - light trap and fogging. The picture you are painting in my mind is that the sealed packages have the moth larva inside them, and whether you are seeing these larva through some clear outer covering on the packages or have to open the package to see the larvae inside really does not change things. Either way if the larvae are inside the packages then misting the air with insecticide is not going to get anything to these hidden, protected larvae and a UV light trap would be only moderately effective on capturing adult moths, if at all. Stored food moths are generally not drawn to light, and in fact adult and larvae of the moths tend to hide from light. 

This is a tough one, but I think that ultimately you need to approach the supplier/vendor of this product - the vendor who is sending their pest problems to your account - and see if something can be done to get it stopped. Somewhere within their production and storage they seem to have a serious moth infestation that needs to be controlled, or they stand to lose an awful lot of business when their customers begin refusing the product or switching to another supplier. You don't indicate what kind of food products these are, but if they are destined for human consumption that vendor with the problems could face some serious financial losses. If it is pet foods the quality control is a bit lower, but even then moth infestations should not be tolerated or they only get worse.

If the problem you have with your customer's packages truly is sealed within the packages then a fumigation would be the only recourse for killing the insects within the packages. This could mean closing the entire facility, tenting it, and fumigating it, or perhaps removing all of the infested material into a chamber or under tarps and having it fumigated separately. However, killing all the moths on your customer's property still does not resolve the issue of more infested material being delivered on the next shipment in from their vendor, so do try to get an interview with that company to see if they are interested in taking care of this. 

If everything fails, and your talks with the vendor fall on deaf ears the, first, shame on them, and second, you will have to do what you have to do, and this means determining what packages are infested and isolating them for fumigation. You can use pheromone traps to help with this, hanging them in the area and seeing which traps get the most adult moths, perhaps narrowing the search. There also are Mating Disruption  pheromones that help to eliminate Indian Meal Moth problems by essentially flooding the warehouse with the mating pheromone to make it impossible for male moths to locate females for mating. This, I believe, is not the best substitute for tackling the problem at its source (the vendor of the products) but does exist as a control option. 


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