UC IPM Online UC ANR home page UC IPM home page


SKIP navigation


How to Manage Pests

UC Pest Management Guidelines

European fruit lecanium.


European Fruit Lecanium

Scientific name: Parthenolecanium corni

(Reviewed 4/10, updated 4/10)

In this Guideline:


European fruit lecanium, also known as the brown apricot scale, occurs throughout the Central Valley, but is rarely a problem. The adult female's domed shell is shiny brown, about 0.4 inch in diameter. Eggs are laid in spring and hatch from May to July. The young develop through the remainder of the season and overwinter on twigs and small branches as partly grown crawlers. There is one generation each year in most areas of the state but a partial second is often seen in the Central Valley.


The chief injury is the production of honeydew that, in large amounts, can damage leaves and fruit. Sooty mold growing in the honeydew can cause blackened areas on leaves and fruit.


Biological control is frequently effective; if treatment is needed, oil applied during dormancy or delayed dormancy is an effective way to reduce populations of this pest and the least disruptive of natural enemies. Increased populations of this scale may appear when dormant sprays are omitted.

Biological Control
Fruit lecanium is frequently kept under control by parasites including Aphytis spp., Coccophagus spp., Encarsia spp., and Metaphycus spp. and predators including lady beetles and lacewings. If present, ants will interfere with biological control; note their presence when monitoring.

Organically Acceptable Methods
Biological control and certain oil sprays are organically acceptable methods.

Monitoring and Treatment Decisions
To determine if a dormant or delayed dormant treatment is warranted, follow sampling and treatment threshold guidelines in DORMANT SHOOT SAMPLING. Look for parasitized scale during the summer by lifting up scale covers as well as examining the covers for exit holes. If a large number of scales are parasitized, treatment may not be needed during the following dormant season.

Common name Amount/Acre** R.E.I.+ P.H.I.+
(trade name) (conc.) (dilute) (hours) (days)

  Calculate impact of pesticide on air quality
When choosing a pesticide, consider information relating to impact on natural enemies and honey bees, the impact of the timing on beneficials, and environmental impact. Not all registered pesticides are listed. Always read label of product being used.
A. DORMANT OIL such as:
  DORMANT FLOWABLE EMULSION 6 gal 1–1.5 gal 4 0
  NARROW RANGE OIL (440 or higher)# 4 gal 1.5 gal 4 0
  MODE OF ACTION: Contact including smothering and barrier effects.
  COMMENTS: Choose a narrow range oil with a 50% distillation point of 440 or higher for dormant season use. Always check with your certifier as to which oils are organically acceptable. Oil alone can control moderate populations of soft scales.
** For dilute applications, rate is per 100 gal water to be applied in 300-500 gal water/acre, according to label; for concentrate applications, use 80-100 gal water/acre, or lower if the label allows.
* Permit required from county agricultural commissioner for purchase or use.
# Acceptable for use on organically grown produce.
+ Restricted entry interval (R.E.I.) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (P.H.I.) is the number of days from treatment to harvest. In some cases the REI exceeds the PHI. The longer of two intervals is the minimum time that must elapse before harvest.



[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Peach
UC ANR Publication 3454
Insects and Mites
W. J. Bentley, UC IPM Program, Kearney Agricultural Center, Parlier
J. K. Hasey, UC Cooperative Extension, Sutter/Yuba counties
K. R. Day, UC Cooperative Extension, Tulare County
Acknowledgment for contributions to the Insects and Mites:
R. E. Rice, Kearney Agricultural Center, Parlier
C. Pickel, UC IPM Program, Sutter/Yuba counties

Top of page

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/r602301411.html revised: April 25, 2014. Contact webmaster.