What's eating my black hickory?

Black hickory faces the same core hickory pest complex as its relatives: pecan weevil destroys nuts from within, hickory bark beetles attack stressed trunks, and phylloxera galls disfigure foliage. Squirrels are relentless nut competitors. Because it grows on dry upland sites, drought stress frequently increases bark-beetle susceptibility.

Larvae feed inside the nut, causing premature drop and hollow, inedible kernels with circular exit holes in the shell. Apply kaolin clay or a labeled insecticide at water-stage nut development; destroy dropped nuts before larvae enter the soil to pupate.

S-shaped larval galleries under bark girdle branches; flagging and die-back most severe on drought-stressed trees. Irrigate during dry spells to reduce stress; prune out infested wood well below the gallery zone and dispose of it off-site.

Spherical galls on leaf midribs and young stems; heavy infestations can defoliate branch tips. Dormant oil before bud break suppresses egg masses; healthy, well-fed trees outgrow moderate phylloxera damage without treatment.