walnut twig beetle
(Pityophthorus juglandis)
This species is Native and Introduced across its range in the United States
Major Hosts:
Black walnut, butternut, English walnut and English hybrids are susceptible.
Key Features:
Disease and Insect: The Geosmithia fungus forms dark cankers on trunks, stems and branches. Adult beetles 1/16 inch, reddish-brown; larvae white, and C-shaped, found under the bark. Lab assays required for positive identification of the fungus.
Damage: Numerous, small bark beetle entrance and exit holes, galleries under bark, numerous dark cankers under bark, branch flagging, crown dieback, and eventually tree death.
Control/Management:
If you suspect TCD you should contact either the Ohio Department of Agriculture, Ohio Division of Forestry or report it using the Great Lakes Early Detection Network smartphone app. There currently is no recommended treatment other than tree removal and destruction.
Black walnut, butternut, English walnut and English hybrids are susceptible.
Key Features:
Disease and Insect: The Geosmithia fungus forms dark cankers on trunks, stems and branches. Adult beetles 1/16 inch, reddish-brown; larvae white, and C-shaped, found under the bark. Lab assays required for positive identification of the fungus.
Damage: Numerous, small bark beetle entrance and exit holes, galleries under bark, numerous dark cankers under bark, branch flagging, crown dieback, and eventually tree death.
Control/Management:
If you suspect TCD you should contact either the Ohio Department of Agriculture, Ohio Division of Forestry or report it using the Great Lakes Early Detection Network smartphone app. There currently is no recommended treatment other than tree removal and destruction.
Selected Images
Invasive Listing Sources
Taxonomic Rank
| Domain: Eukarya |
| Kingdom: Animalia |
| Phylum: Arthropoda |
| Subphylum: Hexapoda |
| Class: Insecta |
| Subclass: Pterygota |
| Infraclass: Neoptera |
| Order: Coleoptera |
| Suborder: Polyphaga |
| Infraorder: Cucujiformia |
| Superfamily: Curculionoidea |
| Family: Curculionidae |
| Subfamily: Scolytinae |
| Tribe: Corthylini |
| Subtribe: Pityophthorina |
| Genus: Pityophthorus |
| Pityophthorus juglandis |
References
Common Name Reference: Bosik, J. J. Common Names of Insects and Related Organisms 1997. Lanham, MD: Entomological Society of America (ESA), 1997. 232 pp.
Scientific Name Reference: R.W. Poole and P. Gentili, Nomina Insecta Nearctica. 1996. Nomina insecta nearctica: a checklist of the insects of North America. Vol. 1-4. Rockville (MD): Entomological Information Services. Available at URL: http://www.nearctica.com/nomina/main.htm