The number of eggs per twig varies greatly. Pupae transform to adults in 10 to 14 days, but newly formed adults may remain in larval tunnels for several days before emerging. During the first half of September, new adults begin to chew out of the old girdled twigs and move to live host trees to feed, girdle, and start a new cycle. Only one generation occurs each year. Damage Typically in Alabama, girdler damage is most common among young hickories in natural stands, and pecans and other hosts maintained as shade and ornamental trees.
Damage is the result of girdling of twigs, small branches, and stems by the adult female.
Structures beyond the girdle die and usually break and fall. Among large established trees, girdling is confined to small twigs in the periphery of the crown. In trees with well-developed crowns, loss of a few twigs among many results in little or no real damage. However, among seedlings, sprouts, and small, young trees, damage can be severe. Girdling of these structures deprives the tree of all or much of its crown.