Leafminers

Also known as: Various Agromyzidae species

Identification

White or pale meandering trails or blotches within leaf tissue. Larvae are tiny (1-3mm) yellow or green maggots visible inside the mine when leaf is held to light.

Damage

Mining — larvae tunnel between leaf cell layers creating visible meandering trails or blotches

Best Organic Solutions (Ranked)

Solutions ranked by reliability tier — start with Tier A options.

Spinosad Tier A

Systemic enough to reach larvae inside mines

Neem Oil Tier A

IGR prevents adult egg-laying and larval development

Biological Controls

Diglyphus isaea (parasitic wasp — punctures mine to reach larva), Dacnusa sibirica

Prevention

Row covers during adult fly activity period. Remove and destroy mined leaves. Sticky traps for adults.

Common Mistake

Contact sprays don't reach larvae inside leaf tissue. Only systemic or translaminar products (spinosad, neem) work against active mines.