Infestation of White Bugs on a Birch Tree

Identification

• Birch trees are prone to infestation from aphids. The soft-bodied, pear-shaped insects are very small in size and are often covered in a woolly to waxy coating. The wingless or winged insects have long legs, antennae and piercing mouths.

Damage

• Aphids use their mouths to suck sap or plant juice from tender plant areas. The pests collect in large numbers on foliage undersides and stems. Damage is characterized by curled, distorted and yellowed foliage. Young shoots are stunted in growth. As they feed, the pests secrete sticky, honeydewlike substance that promotes the growth of sooty mold fungus on affected plant areas.

Control

• Introducing natural predators like parasitic wasps, lacewings and syrphid flies in affected trees is a biological control option for aphids. Prune and remove heavily infested tree areas. Fungicidal control options include the use of acephate, permethrin and malathion.