Trichogramma are effective destroyers of caterpillar and moth eggs, including the eggs of bollworms, tobacco budworms, codling moths, corn earworms, alfalfa caterpillars, gypsy moths, cutworms and tomato hornworms. Trichogramma lay their eggs inside the caterpillar or moth eggs. When the trichogramma hatch, they feed on the caterpillar or moth eggs, then emerge as adults to continue the cycle. Each container includes 4,000 eggs (three containers per order). Gardeners simply mail in the postcards or register online to have their insect orders shipped to their doors at no extra cost.