Pest profile

Beech Blight Aphid

Grylloprociphilus imbricator · Hemiptera: Aphididae[3]

Beech blight aphids form white, fluffy colonies on American beech branches; when disturbed the nymphs wave their abdomens in unison, earning them the name boogie-woogie aphids, and their honeydew grows thick black sooty mold below.[1][2]

Colony of beech blight aphids along a beech branch, covered in white waxy tufts
Colony of beech blight aphids along a beech branch, covered in white waxy tufts. (c) Katja Schulz, some rights reserved (CC BY) — via iNaturalist, CC BY 4.0

How to identify it

  • Aphids are bluish gray, with the rear of the abdomen hidden by a dense white fluffy secretion and long white filaments.[1][2]
  • Colonies can grow so large that a white mass extends up to five feet along a branch.[1]
  • When a colony is disturbed, nymphs lift their abdomens and thrash in unison.[1][2]

Where it lives

NC State and Clemson report it on American beech in the Carolinas; it alternates between beech and bald cypress.[1][2]

US map: public records from 28 states since 1990 (GBIF).

Biology and life cycle

It spends the winter on bald cypress roots, then flies to beech to lay eggs for the spring generation.[1][2]

Colonies persist on beech from April through November in North Carolina; winged aphids leave in summer and fall for bald cypress.[1]

Nymphs can use their mouthparts to jab predators, and may even jab a person who lets them touch bare skin.[1]

Damage and signs

  • Damage to the beech is minimal; the main problem is honeydew and the sooty mold growing on it.[1][2]
  • The sooty mold, Scorias spongiosa, forms an unusually thick, spongy mass that starts honey-colored and turns black, blanketing plants below.[1][2]

Health risk

Not a health risk, though nymphs may jab skin that touches a colony.[1]

Control

Biological control

Populations are sometimes wiped out by an insect-infecting fungus and are attacked by parasites and predators.[1]

Pesticides

Where control is wanted, pyrethroids, horticultural oil (weather permitting) or insecticidal soap should suppress them; keep pyrethroids away from pools, ponds and streams.[1]

Common questions

What is the white fuzz on my beech tree branches?
Usually colonies of beech blight aphid nymphs covered in white waxy filaments.[1][2]
Will beech blight aphids kill my tree?
No; damage to the beech is minimal, though the sooty mold below is unsightly.[2]
Why do the aphids dance?
Disturbed nymphs raise and wave their abdomens together, apparently as a warning to predators.[1][2]

Sources

  1. NC State Extension, “Beech Blight Aphid (PDIC Factsheet).” content.ces.ncsu.edu/beech-blight-aphid (accessed 2026-10-15)
  2. Clemson Cooperative Extension, Home & Garden Information Center, “The Beech Blight Aphid Nymphs.” hgic.clemson.edu/the-beech-blight-aphid-nymphs/ (accessed 2026-10-15)
  3. iNaturalist, “Grylloprociphilus imbricator taxon page (order and family).” www.inaturalist.org/taxa/146709 (accessed 2026-10-06)

Updated 2026-10-15. Built from sourced records. Spot an error? Tell us.