The Citrus Leafminer (Phyllocnitis citrella) has been very active on the new growth of Santa Barbara citrus trees this year. Their larvae tunnel mines inside the leaves distorting growth. The adult form can fly between trees and travel on wind currents.
Mature trees may withstand an invasion but the growth of young trees may be retarded with heavy prolonged infestation.
Where possible infested areas may simply be cut out.
Organic spray Spinosad is labeled for use on Citrus leafminer. It is a naturally occurring compound produced by a bacterium and is translocated into leaves.
Parasitic Wasps are Leafminers’ natural enemies. Populations will increase and ultimately provide biological control.