Pest Profile Photo credit: Dick Wilson, Bugguide.net Common Name: Maple Twig Borer Scientific Name: Proteoteras aesculana Order and Family: Lepidoptera: Tortricidae Size and Appearance: Length (mm) Appearance Egg > 1 mm Small, dark in color laid on emerging leaves at bud break. Larva/Nymph 10 mm White to grayish white in color with a yellowish head. Head tends to be noticeably wide at 1.1 mm. Dark spindles present. Adult 11-18 mm Brown/olive in color, mottled with yellow markings. Small in size. Pupa (if applicable) 8-10 mm Pupate on bark on protected side of tree. Type of feeder (Chewing, sucking, etc.): The juvenile form of P. aesculana features chewing mouthparts that are used to feed on tender buds and seeds in both the fall and spring. Host plant/s: The Maple Twig Borer will consume the new growth of Maple, Silver Maple, Sugar Maple and Bigleaf Maple. In nursery situations, they have been known to feed on Boxelder and other Acer species. Description of Damage (larvae and adults): During growing season, the larvae bore into the shoots, which prevents any new growth. The frass they produce while in the shoots mixes with webbing. This practice combined with feeding can cause deformities such as forks in the stem. Heavy infestations are often similar in appearance to heavy frost damage and trees can be permanently disfigured. Removing infected limbs can help with control of this pest. References: Cranshaw, W. (2004). Garden Insects of North America: The Ultimate Guide To Backyard Bugs. (pp. 442- 444). Princeton, NJ: Princeton University Press. Vanek, S.(2011). Maple Shoot Borer: Biology and Management of a Prominent Nursery Pest. University of Kentucky Extension. 9 March 2012. https://entomology.ca.uky.edu/ef455 Solomon, J.D. (1995). Guide to Insect Borers in North American Broadleaf Trees and Shrubs. Agriculture Handbook 706. Washington, DC. United States Department of Agriculture, Forest Service. 735 p. .