Dispersal and colonization risk of the Walnut Twig Beetle, Pityophthorus juglandis, in southern Europe

Phylogeography of the Walnut Twig Beetle, Pityophthorus juglandis, the Vector of Thousand Cankers Disease in North American Walnut Trees

Thousand cankers disease (TCD) of walnut trees (Juglans spp.) results from aggressive feeding in the phloem by the walnut twig beetle (WTB), Pityophthorus juglandis, accompanied by inoculation of its galleries with a pathogenic fungus, Geosmithia morbida. In 1960, WTB was only known from four U.S. counties (in Arizona, California, and New Mexico), but the species has now (2014) invaded over 115...

Insecticide Dip Treatments to Prevent Walnut Twig Beetle Colonization of Black Walnut Logs

The health, sustainability, and commercial viability of eastern black walnut (Juglans nigra) are currently under threat from thousand cankers disease. The disease is caused by an invasive bark beetle species, the walnut twig beetle (Pityophthorus juglandis), and its associated fungal pathogen (Geosmithia morbida). Range expansion of the beetle and pathogen has likely been facilitated by transpo...

Studies on the Walnut Twig Beetle (wtb), Pityophthorus Juglandis, in Relation to Its Association with Geosmithia Morbida, Its Survival in Felled Logs, and Its Sensitivity to Temperature Extremes

Walnut Twig Beetle (Coleoptera: Curculionidae: Scolytinae) Colonization of Eastern Black Walnut Nursery Trees

Thousand cankers disease, caused by the invasive bark beetle Pityophthorus juglandis Blackman and an associated fungal pathogen Geosmithia morbida M.Kolařík, E. Freeland, C. Utley, N. Tisserat, currently threatens the health of eastern black walnut (Juglans nigra L.) in North America. Both the beetle and pathogen have expanded beyond their native range via transport of infested walnut wood. Geo...

Questions and Answers about Thousand Cankers Disease of Walnut

What is thousand cankers disease of walnut? Thousand caners disease (TCD) is a newly recognized disease (2008) of certain walnut species (Juglans) caused by a fungus (Geosmithia morbida) that is vectored by a bark beetle (Pityophthorus juglandis, the “walnut twig beetle”). Thousand cankers disease has produced widespread death of walnuts in many western states during the past decade. In recent ...