Tomato, tobacco, legumes, cucurbits, sweet potatoes and banana are a few of the most susceptible plants, but it will also infect other herbaceous plants.
Herbaceous and shrubby subalpine meadow vegetation and scattered patches of mountain hemlock, subalpine fir, and whitebark pine occur near the timberline.
They are perennial herbaceous plants which grow up to 2.5m ft tall, having distinctive small green or white flowers arranged in an umbrella shape (umbel).