Small White Bugs on Tree Bark

Small white bugs on your tree's bark may cause more than just aesthetic problems. Insects such as scales, aphids, mealybugs and gypsy moths feed on your tree's vegetation. In addition, small white bugs can cause major damage when your tree's leaves begin to defoliate and loose the ability to photosynthesize. Identification is essential to pick the correct treatment.

Aphids are nutrient-sucking insects that feast on the leaves of trees and other ornamental plants. They can cause leaf curl, leaf yellowing and stunted shoots. While most are black or brown, some species are white because of a waxy substance they secrete on their body, according to the University of California. In fact, aphids secrete another substance called honeydew. Honeydew is left on the branches and leaves of trees. Fungal spores and diseases such as sooty mold stick on the honeydew and cause additional tree problems. Gardeners should spray the honeydew off their trees before applying a pesticide to treat the aphids.

Scales are tiny insects that suck the nutrients out of the foliage of leaves. Trees that have been heavily infested with scales will have unhealthy growth or very little new growth, according to the University of Florida. Left to their own devices, scales will cause trees to defoliate. Furthermore, scales produce honeydew like aphids, which can cause your tree to contract sooty mold. Treatment should begin when scales are in their crawler phase or when they are young. Because their a several generations of scales every year, you should repeat applications of pesticide each season as directed.

Mealybugs are part of the scale family. They look cottony from the white filaments that grow off of their bodies. These pests feed off of leaves, branches, stems and roots. Trees begin to display distorted growth, deformed leaves and yellowing foliage. Gardeners with mealybug problems should prune off damage. Moreover, reducing the small twigs and leaves inside of the tree will aid in pesticide applications. Spray the tree with a pesticide and monitor the plant for more mealybugs.

Gardeners who notice white gypsy moths on their bark are dealing with the females; yet, undoubtedly, their male counterparts are nearby. Female gypsy moths lay their eggs on trees. When their eggs hatch, the larvae move to the crown of the tree at night and eat the foliage. According to the U.S. Department of Agriculture Forest Service, gypsy moth larvae have caused almost one million trees to completely defoliate in a year. Trees that have been infested by gypsy moths must be treated with insecticide. In addition, old wood, tires, boxes, cans and anywhere gypsy moths can nest should be removed from the yard to prevent future damage.