9ac1836f_Pests___Diseases__Problem_Symptom
[Cause] Canker, a fungus disease. The fungus spreads in water and enters the plant through cuts or wounds in the canes. The problem is most severe in early to middle spring, when plants come out of dormancy. [Solution] There is no chemical preventive or cure for canker. When symptoms appear, prune infected canes below the canker. Use sharp pruning shears and make the cut just above a node at a 45 degree angle. [Problem/Symptom] 
Red or brown sunken spots with dark margins develop on canes. Cracks may appear within the spots. The spots enlarge and eventually encircle the cane. Leaves and stems above the damaged area turn yellow, wilt and die.
Pests & Diseases
Problem/Symptom