I am going to assume that this is an apple tree because they favor them.....I am very protective of our fruit trees. I went out there before the sun when down & I used Pam with a straw to put thru the 3 layers of the bag worms........going all the way in and then spraying out fast...............that kills them.....then early the next morning I took a stick and a bag and got the whole mess off the tree and wiped the branch with a damp towel to get the rest of the mess off...........in the fall after the fruit is picked spray with dormant oil..........follow the directions on the bottle for the type of tree......in the spring follow the spring mix........and I spray all the way up to the bud stage....one it opens I do not spray the flowers because it will kill the bees..........I only spray the trunk.............there is a summer mix..........so follow the directions on the container. Wear long clothing, mask, goggles, hat and gloves. Don't spray if it is going to rain or if it is windy.........................keep children & pets away from the area until it is dry...............Do not throw this mix down any drains...........use it all on the trees.