HOST PLANTS: Blue Colorado Spruce is the primary host. Norway Spruce is resistant. Other spruces and pines are infrequently attacked. DAMAGE: Symptoms of needlecast appear between early spring and early summer when needles infected the previous season turn purple or...
HOST: Crabapples and apple vary widely in their resistance to scab. Related (but different) species of the fungus that cause apple scab produce scab on hawthorn, mountain ash and pyracantha. DAMAGE: Apple scab describes the disease as it appears on the disfigured host...
HOST PLANTS: Boxwoods DAMAGE: Boxwood blight, caused by a fungus, is a devastating disease affecting boxwood plants. First identified in the mid-1990s, this pathogen has since spread across regions, becoming a major concern for gardeners, landscapers, and...
