What's eating my shagbark hickory?

Shagbark hickory is attacked by hickory shuckworm, pecan weevil relatives (Curculio hickoriae), and hickory bark beetles, which bore under stressed bark. The distinctive shaggy bark harbors overwintering pests. Squirrels are the chief crop raiders and can take nearly the entire nut yield. Fall webworm routinely forms webs on terminal branches in summer.

Early-generation larvae mine leaf petioles; later generations bore directly into the developing husk and sometimes the nut, causing premature drop and distorted nuts. Apply spinosad or carbaryl at first adult flight (pheromone traps); repeat at 10–14 day intervals during nut development; remove fallen infested nuts.

Adults puncture developing nuts with their snout to feed and lay eggs; larvae consume the kernel; infested nuts drop in mid-summer long before maturity. Carbaryl sprays beginning at late-June nut sizing; collect and destroy all dropped nuts immediately to reduce the next generation's soil emergence.

Silken tents at branch ends house feeding caterpillars; mature shagbark trees tolerate damage well, but young trees can be repeatedly defoliated. Prune and destroy nests while small; Bt or spinosad applications into open webs; no chemical treatment needed on established trees with minor infestations.

Squirrels harvest shagbark nuts at or before natural drop; cached nuts are rarely recovered at usable rate; a family of squirrels can strip a tree in days. Metal trunk collars; live trapping in September–October; harvest at first natural nut fall and hull immediately.