WSU Extension programs and employment are available to all without discrimination. Evidence of noncompliance may be reported through your local Extension office.
Juniper : Leafminers
categories: Conifers Juniper Juniper Insects Ornamentals
revision date: 2022-11-05 08:05
Photo by: A.L. Antonelli
Biology
Various species of leafminers may occur on junipers. In general, the damage they produce is very similar to that of the cypress tip moth. Damage is typically limited to tips of twigs, which are fed upon from the inside. Damaged leaves and twigs turn brown and webbing and dark pellets of frass (excrement) may be visible. Heavy infestations can cause severe damage.
Management Options
Use Integrated Pest Management (IPM) for successful plant problem management.
Non-chemical Management
Select non-chemical management options as your first choice!
- Several naturally-occurring parasites help control leafminer populations. Try to avoid use of broad-spectrum insecticides to conserve the parasites.
- Remove damaged portions of plant to improve appearance (when practical).
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
- Apply thoroughly to new growth as a protective spray.
- Apply at end of May and again in mid-June.
- Follow label instructions for products applied as a drench.
- Homeowners should not make foliar applications to trees over 10 ft tall.
- Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.
Additional Images
Photo by: R.S. Byther
Photo by: A.L. Antonelli
WSU Extension programs and employment are available to all without discrimination.
Evidence of noncompliance may be reported through your local Extension office.