Sphaerulina rubi

Raspberry leaf spot is a plant disease caused by Sphaerulina rubi (syn. Cylindrosporium rubi), an ascomycete fungus. Early symptoms of infection are dark green spots on young leaves. As the disease progresses, these spots turn tan or gray in color. Disease management strategies for raspberry leaf spots include the use of genetically resistant raspberry plant varieties, chemical fungicide sprays, and cultural practices such as pruning and thinning out canes. Raspberries are an important fruit, mainly grown in Washington, Oregon and California. Although they are also grown in the Midwest and northeastern states, the output is not nearly as great due to the colder weathers and shorter growing seasons. S. rubi prefers warmer and wetter conditions, which can make raspberry production very difficult in California....read more on Wikipedia.