What are common signs of insect or disease damage on ornamentals that may require pesticide treatment?

• A. Yellowing, spots on leaves, leaf drop, abnormal growth, visible pests or fungal growth such as powdery mildew.
• B. Only green leaves remain.
• C. Increased flower production.
• D. Strange root scent.

Answer: (A)

Signs of insect or disease damage on ornamentals that may warrant pesticide treatment include yellowing of leaves, spots on leaves, leaf drop, abnormal growth, and the appearance of visible pests or fungal growth such as powdery mildew. Yellowing can result from pest feeding or disease disrupting the plant’s chlorophyll; leaf spots are typical of fungal or bacterial infections or feeding damage; leaf drop shows that the plant is under severe stress from pests or pathogens; abnormal growth covers distortion or stunting caused by ongoing infestation or infection; and seeing actual pests or a fungal film confirms active problems. When these symptoms appear, it's a cue to inspect more closely and follow label directions for management, which may involve a pesticide if appropriate. The other options don’t fit because purely green leaves usually indicate healthy plants, increased flower production is not a typical sign of pest or disease damage, and a strange root scent points to root issues rather than common above-ground insect or disease activity.