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

Fig. 3. Percentage of the total number of black walnuts that were removed in Boulder (black line) and Denver (gray line), Colorado, 2001-2010. Percentages are based on total black walnut inventories determined by detailed visual surveys in both cities.



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