Pistachio Tree Sticky Honeydew: Aphid or Scale Infestation

Identifying the Source

Gluelike sticky film on pistachio leaves = honeydew from sap-feeding insects—aphids (soft, round, on leaf undersides) or scale (oval shields on stems, scrapeable). Black sooty mold may follow.

Safe Control Options

• Safer's Insecticidal Soap—spray undersides/stems; safe, no residue.
• Dish soap (risky)—may strip leaf wax, cause wilting.
• Stronger insecticides—if infestation heavy; consult local guidelines.

Key Inspection Points

• Leaf undersides → aphids.
• Stems/branches → scale.
• Both produce honeydew → sooty mold (harmless, cosmetic).

Early soap treatment prevents buildup. Pistachio's edible nuts favor low-toxicity options.