Safer Brand Caterpillar Killer with BT, 8 Ounce Concentrate Kills caterpillars, gypsy moth larvae, worms and cabbage loopers Effective method of eliminating your garden or field of the tomato hornworm without environmental concerns or harm to wildlife and beneficial insects. It is recommended that this product be applied late in the afternoon or on cloudy days since B.t. breaks down in the sunlight. Safer Brand is the leader in alternative lawn and garden products Contains Dipel (bacillus thuringiensis var Kurstaki -- 1.76%)