- Insects – may include chewing or boring into leaves and stems, or plant parts missing altogether. Leaves may be curled, skeletonized (only the leaf veins remain while the tissue between the veins is missing) or have dead spots from insect feeding. Insects may also spread bacterial, fungal, or viral diseases from plant to plant.
- Pathogens (diseases) – includes viruses, bacteria and fungi. Leaves may have circular or irregular patterns of dead or discolored tissue or be completely covered in spores from fungi.
- Non-infectious (physiological) – includes nutrient deficiencies and toxicities, environmental stresses, or damage caused by chemicals, animals, weather or equipment
Five Steps to Complete When Diagnosing Plant Problems
- Identify the plants species and cultivar if applicable – Determine if growth is normal? Did the plant grow abnormally this year, or did it grow at all? What is the leaf shape and size compared to ideal?
- Look for patterns – Are other plants in the area affected too? Are the symptoms uniform or random? Is more than one species affected?
- Determine what part(s) of the plant are affected – Are the roots, stem, leaves or branches affected? How has the damage progressed over time?
- Look for visible symptoms (abnormal appearances or characteristics of plants) and signs (indirect or direct evidence of a pathogen or insect) – chlorotic (yellowing of plant foliage), necrotic (browning and death of plant foliage), contorted growth, damaged or missing parts. What are the leaf patterns and color? Are any signs of the insect or disease (visible insect body parts or fungus spores) present?
- What are the environmental and cultural situations present? Ask questions about management practices (watering and fertilizing), history of the area, weather, soil, and handling of the plant. Find out the current history of the area where the plants are growing. What fertilizers or pesticides have been used? What is the irrigation system and how much/how little water has been applied and when?
August 13, 2012