Thousand Cankers Disease is Widespread in Black Walnut in the Western United States

Fig. 1. Thousand cankers disease was identified in black walnut (Juglans nigra) or hybrids (Oregon only) of black walnut with northern California black walnut (J. hindsii), in (A, shown here) Colorado in 2008 and (B) Oregon in 2009, although walnut decline had been noted in Oregon since the early 1990s. Thousand cankers distribution in the western United States has expanded with confirmations in (C) Washington in 2009 and (D) and Idaho in 2010.



Image from Plant Health Progress article:
Thousand Cankers Disease is Widespread in Black Walnut in the Western United States