So, I mentioned a couple weeks ago that I was going to work up the nerve to try the natural predatory wasps that are supposed to eat pantry moth eggs. I first heard of the wasps a couple years ago when one of my customers suggested that she might try them. I was pretty shocked- I had never heard of the moths and also was pretty horrified at the thought of setting a bunch of wasps lose in the house to get rid of moths...??!! Aren't wasps a bigger pest than the stupid moths?? At least the moths don't sting! But, in the name of all things pantry moth, I decided to face my fear and see if I could manage the wasps- to give you a first-hand account of how they are.
I intentionally developed a bit of a pantry moth infestation (which is terrifying to those of us who have HAD a real pantry moth infestation...) I know now that Aunt Norma's Pantry moth spray and pantry moth trap will get rid of pantry moths, so I wasn't too worried, but made sure to keep my grains in the freezer (except for a few things left out to feed the moths) just in case. I researched several places to order the wasps, and finally decided on a place that was still able to ship them into the fall (most places only harvest/ sell the moths in the summer/ spring... so they are hard to get in the fall or winter- they are generally available from March 1st-September 1st). They weren't very expensive (under $15.00), but I was surprised that the delivery was delayed a couple weeks- it seems that the wasp nursery must be a bit temperamental. I began getting a little nervous with the delay in the delivery, as I was anxiously watching the pantry moth infestation starting to get a little out of hand. I DID finally cave in and put out a pantry moth trap so that the infestation wouldn't get unmanageable before the wasps arrived.
So the wasps arrived in a plainly wrapped paper bag, labeled "Trichogramma". The man assured me when I ordered, that these wasps are tiny and that I likely wouldn't even notice them in my kitchen. I opened the bag to find tiny little cups, and placed them in my refrigerator until I had time to read the instructions. The package sat outside my door for a day- so I hope the wasps are still OK. According to the instructions, the trichogramma wasps come inside the pantry moth eggs...which freaked me out a bit as I realized that meant that I had really just been sent a sh##load of pantry moth eggs! This better work.
The Trichogramma Wasps attack and destroy pantry moth eggs. Shipped as pupae in the host eggs, glued to one inch paper squares, the Trichogramma arrive ready to hatch out as adults wasps. The instructions state to "Release 5,000 per 5,000 square feet weekly, for 3-6 weeks."
"Wait- did I read that right.... 5,000 wasps??!!" I must admit that this is probably one of the scariest things I've done. Even if they are TINY- this means that I am releasing 15,000 wasps (there are 5000 to a dish, and I received three of these...) in my freaking KITCHEN????
They arrived stuck on small bits of paper that look like strips of sand paper inside plastic cups. These are the moth eggs (tiny little things) that the wasp are attached to...? If I am understanding the instructions. Really- they just look like little bits of dirt in a cup. Supposedly, they eat the eggs! EW!! But this means that they spend all of their time flying around searching nooks and crannies for the eggs. (I get like this when am on a diet and hide chocolate from myself... hunger is a pretty BIG motivator!) The tiny beneficial insects are claimed to be effective because they prevent the pest from reaching the destructive larval stage. The instructions state that the wasps will not be a nuisance to people or pets. They are supposed to be extremely small and "you will not even notice them". Well, in the pictures I've found, they look terrifying! Also- they are supposed to leave once they have eaten all the moth eggs.
I placed the little plastic cups with the wasps inside in my pantry and waited. I will say that I didn't really notice tons of wasps flying around- but I definitely DID see them. They would be on the counter- I also continued to see moths flying around- so I guess the wasps didn't arrive in time to get all the eggs before they hatched. As with any moth treatment, it can take up to 3 weeks for the moths leftover to complete their life cycle (since the wasps only eat eggs- the larvae or moths that are already there will NOT be killed and you will have to wait for them to die off on their own, or put out a pantry moth trap or use Aunt Norma's Pantry Moth Spray.
It has been about a month since I released the wasps (and, technically, I didn't really do it right b/c I released all 15,000 wasps at once instead of spread out over a few weeks- I guess I misread the directions the first time around.) I am still seeing the occasional pantry moth flying around, but I definitely am not seeing the volume of moths that I know would be taking over my kitchen had I not intervened. I am going to conclude, for now, that the wasps WERE effective. I should wait another month to make sure that I don't get another round of moths (which would probably not happen if I had followed the instructions correctly), but for now- it appears that the wasps worked. I'm not sure that Trichogramma wasps are for everyone, creating a food chain in the state of nature in your kitchen is not for the squeamish!
I would love to hear anyone else's thoughts or personal experience with these wasps. Please comment below!