How to Manage Pests

Pests in Gardens and Landscapes

Parasites of tentiform leafminer

Several parasitic wasps help control the leafminer. Parasite activity is usually highest and easiest to see following an outbreak of leafminers. The actual level of parasitization is highest, however, when leafminer populations are low.

Female parasites usually lay their eggs in the leaf mine formed at the beginning of the tissue-feeding stage. After hatching, parasitic larvae generally attach themselves to the outside of fourth- or fifth-instar leafminers. The parasite grows rapidly and consumes the leafminer by its fifth instar. It then pupates within the leaf mine, at about the same time as the leafminer would have. Although smaller than a leafminer pupa, the parasite pupa can be distinguished by its larger head and eyes and flattened body. Following pupation, the adult parasite cuts a hole in the leaf and emerges. Adult parasites are small but easy to spot when populations are abundant because they fly in groups that hover near infested trees. Adult parasites feed on the sap-feeding leafminers.

A leafminer parasite larva
A leafminer parasite larva

Parasite pupa (bottom) and leafminer pupaParasite pupa (bottom) and leafminer pupa


Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2014 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   /PMG/GARDEN/FRUIT/PESTS/parasites.html revised: April 25, 2014. Contact webmaster.