I had a bag of bird seed for wild birds out in the garage, unopened, and when it came time to use it, weevils had turned all the safflower seed to dust and were crawling all over inside the bag. They did not touch the black sunflower, corn, or other seed in the mix. I put the seed in tight lidded metal containers and waited until it froze real good before using it again. I figured any weevil bodies in there, the birds could eat.