Holly trees with their uniquely shaped leaves and bright red berries remind many of Christmas. They have long been used on Christmas cards and decorations to symbolize that special season. The trees tolerate heat and cold well. They can be found on much of the landscape as forest cover, individual trees in home gardens, fences or borders. Although generally quite hardy, holly trees are susceptible to attacks by insect pests. Following is a guide on insects that tend to attack hollies and control measures that you can take.
These are small light yellow maggots. They frequently attack holly trees. The adult leaf miner makes slits on the leaf surface where it lays eggs in the early summer. As they feed, the maggots create small ridges on the leaf surface. The ridges gradually increase in size and become mines. With severe infestation, white blotches and blisters develop on the leaves. Leaves eventually become brown, roll back and die. Remove and get rid off all affected leaves. If necessary, prune back branches until you've cleared all infected parts. Use screening to cover your hollies so that leaf miners do not settle onto your trees and lay eggs. Nylon netting is a good screening material to use. Take precautions to cover young seedlings and new transplants. You can also install yellow sticky traps amongst your trees to capture the leaf miners. These are small yellow strips that are coated with a sticky non-toxic substance.
These small insects are yellow in color. They settle underneath the leaves as well as on branches to draw plant sap. As the scales multiply and feed, yellow spots and brown lumps develop on the leaves. The branches also develop small brown bumps. Scales secrete honeydew as they feed which encourages sooty mold to develop. Spray your hollies with insecticidal soap to eliminate scales.
These tiny insects can be difficult to spot. They attack in the spring and fall. Leaves become discolored and deformed. When mites attack your hollies, you will notice small yellow or red spots on the leaf surface. The mites usually create a fine web over affected plant parts. The insects do not like wet conditions so be sure to provide enough water for your hollies. You can use a strong spray of water on affected plants to contain spreading of mites. Ensure that there is good circulation of air amongst your hollies as mites thrive where air circulation is restricted.
Holly Bud Moth
These small moths measure about half an inch in size. They are grey in color and mottled with brown. They usually attack leaves of the holly tree, causing them to turn brown in color. The Holly Bud Moth lays eggs in the summer and early fall. Larvae hatch in the spring. They measure about ½ inch and are yellowish-greenish in color. Larvae attack the leaves during the summer and lump the leaves in black or brown masses. Plant varieties of hollies that are moth resistant. If the infestation is mild, you can handpick the moths. Otherwise, a fungicide can be used to eradicate.