Description
    Several species of plant hoppers have been found on black walnut, the most common of which are Anormenis septentrionalis (Spinola) and Metcalfa pruinosa (Say).

    The nymphs of both species are similar in color and size. They resemble small fluffy masses of cotton because of white waxy secretions they deposit around themselves and on the plant. Adults of Metcalfa pruinosa are dark blue-black in color, sometimes with a white,powdery substance obscuring the color. Anormenis septentrionalis adults are green to yellow-green. Both species are approximately 1/4 inch long and they hold their wings flat against the sides of their bodies. Plant hoppers are noted for their ability to jump when disturbed.

Injury
    Adults and nymphs are sucking insects, feeding on sap taken from leaves and stems of smaller twigs. Feeding damage is considered insignificant. The female adult, however, may cause the tips of small twigs to die when she deposits her eggs in zipper-like slits beneath the bark.

Control
    Control is usually not necessary.