The characteristic black spots on infected leaves are patches of fungus, not dead tissue. The organism attacks only roses; it survives on canes and fallen leaves, then spreads easily during misty, foggy, or rainy weather. Black spot is common in regions where summer weather is warm and humid.
Roughly circular black spots with ragged yellowish borders appear on leaves. In severe cases, defoliation occurs.Control:
Fungicides, disease controlNotes:
Water early in the day; avoid working among wet plants. Remove and destroy infected leaves.