I got those nasty worms on my tomatoes one year, and didn't know what to do. (And I didn't have chickens!) My father - the kind of gardener who can poke a dead stick into the ground and it will sprout something amazing and edible - told me to wrap newspaper around the base of each plant and secure it. They don't like the newspaper, and won't climb the plant. I never had another problem with the worms.