preventing paper wasp nests in bird nest boxes

Hello birdlovers...I am in the Hudson Valley, and we have a house that was built in what was formerly a corn field. We put up fence...have several sets of bluebirds each year (!!!). Last year we watched as a bluebird couple successfully raised their 3 , and watched them all fledge. Well, I recently went out in the yard to clean out the boxes. Found a large paper wasp nest in a box, pulled out chunks of it, about 40 or so live wasps were overwintering. They were no threat to me, as it was still quite cold, they were sluggish, and they quickly died from exposure, but they were very much alive. Does anyone have suggestions about how to prevent wasps from building their nests inside my birdboxes? I read a suggestion in Birds and Blooms mag to rub the inside of the boxes with soap to prevent the wasps from adhering their paper to the top and sides of the box, but it was impossible to get the bar soap in the corners and crevices of the boxes. I am looking for advice, help! Lottabeds from the Hudson Valley

Hi lottabeds, Here is a page from the Sialis website on dealing with paper wasps. Scroll down for some answers.

http://www.sialis.org/paperwasp.htm

Dear Pelletory, Thanks for such a prompt and very comprehensive reply! No question about it, it is the European wasp that we see so much of here, and that was in the box. Why or how is it that this creature was introduced over here? I see plenty of our brown native variety early on in the season, but eventually these yellow striped buggers outnumber others. No others...no hornets so far in our yard. Had quite an infestation of giant locust killer wasps a few years ago...what a site...back to the Europeans...I will follow the advice on the link you provided. I have watched with fascination in past years the wasp landing on a caterpillar, stinging it (I guess!) rolling it about like a pizza dough ball, and taking off with the thing. I let it go and dont kill the things because of their obvious beneficial aspect. We grow nicotiana every year, love the aroma, and we know how the moths love it. On with the vaseline et al! Lottabeds