European shot-hole borer

The European shot-hole borer, Xyleborus dispar, lives up to its name leaving trees with small diameter holes resembling tiny shot holes. A current investigation of borer activity in Oregon nurseries indicates that this species of ambrosia beetle is active in various sites in the Willamette Valley. We've identified this borer in current season damage from container and field production sites. Click the hyperlink below to see a very informative website regarding this beetle.

http://www.wcga.net/shb.htm

The Ministry of Agriculture, Food, and Fisheries in British Columbia also has some photos of the beetles and damage:

Ministry of Ag website

There is a nice large photo of the adult female by the Canadian Forest Service.

The HYYP Zoologea website also has nice photos at the bottom of the page (website language is French).

The beetle has a large host range. Hosts include: Acer, Aesculus, Alnus, Betula, Castanea, Crataegus, Corylus, Cydonia, Fagus, Fraxinus, Juglans, Leriodendron, Magnolia, Malus, Platanus, Populus, Prunus, Punica, Pyrus, Quercus, Salix, Ulmus, and Vitis. There are also reports from Pinus, Cedrus, and cedar, and Tsuga. Check for current damage in trees which might have experienced stress. Sap weeping from the small diameter wounds is one symptom readily seen. These beetles often appear in large numbers even on the same tree.

We have found it extremely helpful for growers with a history of shothole borers to monitor flights of the borers. The Lindgren funnel trap with an ethanol lure (Pherotech) was used successfully in our research to obtain flight data for several common borers.

Literature cited:
Schuh, J. and D.C. Mote. 1948. Insect Pests of Nursery and Ornamental Trees and Shrubs in Oregon.

H. Omroa Bhagwandin, Jr. The Shothole Borer: An Ambrosia Beetle of Concern for
Chestnut Orcharding in the Pacific Northwest. Western Chestnut Growers Assn. Website http://wcga.net/shb.htm

Page last modified 3/14/08