You could trim them in the spring.....also use dormant oil fall and spring up to the bud stage............after the bud opens the bees come....I stop spraying...........just spray the trunk. Read the container carefully, wear old long clothes, goggles, hat, gloves and mask. Keep children & pets away from this area until it is dry. Don't spray on windy days or when it is going to rain. Test the soil, use lime and old horse manure in a ring away from the stem about 20 inches. You also need to check the PH it should be 6.0-8.0