Myzocallis coryli (Filbert aphid)
Small, soft-bodied, and light to dark green in color. Adults are approximately one-tenth inch long and nymphs are about half the size of adults. Eggs are pale yellow when first laid, and turn to shiny black before hatching in the spring. They are oval in shape and round at both ends. Newly hatches nymphs vary in color from white to pale yellow.
Biology and Damage
Aphid overwinters as an egg that hatch early in the spring. Egg hatch may begin as early as March1 and continue 3 t 4 weeks. They molt four times and produce winged adults that give birth to young aphids without sexual reproduction. In early spring, aphids can be found on unfolding buds; later they occur on the undersides of leaves. All stages of leaf growth may be infested, although a slight preference is seen for younger leaves. Upon maturation, particularly during cool, moist weather. In July and August, aphid numbers decline because of high temperatures. In the fall aphid produce the egg-laying forms that occur in October and deposit the overwintering eggs on the tree and branches.
Damage is caused by large numbers of aphids feeding on the foliage and removing plant sap with their sucking mouthparts. Feeding damage reduces tree vigor and quality of the nuts produced. Aphids also secrete latge quantities of honeydew which may cause severe leaf burn, scorch, or staining of the nuts.
USA: Filbert aphid TR: Fındık Yaprakbiti