UC IPM Online UC ANR home page UC IPM home page

UC IPM Home

Search

SKIP navigation
How to Manage Pests

Home & garden
Agriculture
Natural environments
Exotic & invasive

Weather data & products
Degree-days
Interactive tools & models

Educational Resources

Publications & more
Workshops and events
PCA exam helper
Pesticide information

Research and IPM

Grants programs
Funded-project results

 
  Printer-friendly version

How to Manage Pests

UC Pest Management Guidelines

| More pests | More crops | About guidelines |

Larvae of pear sawfly, also known as cherry slug or pear slug, leave behind lower epidermis and leaf veins when feeding on leaves.

Cherry

Cherry Slug

Scientific Name: Caliroa cerasi

(Reviewed 4/06, updated 4/06)

In this Guideline:

DESCRIPTION OF THE PEST

Adults are small, glossy black sawflies about 0.2 inch long. The newly hatched larvae are white with a yellowish brown head. Almost immediately after hatching, the larva exudes an olive green coating that covers its body and gives it the appearance of a slug. The head end is wider than the rest of the body and a fully mature larva is about 0.5 inch long. Cherry slugs overwinter as pupae in the soil. There are two generations a year with adults emerging in July to lay eggs of the next generation that overwinters.

DAMAGE

Cherry slugs are a pest of cherries in coastal areas. Larvae skeletonize leaves and may remove all tissue except for the fine network of veins. High populations may reduce fruit size.

MANAGEMENT

Inspect foliage in spring, and treat if high numbers are found.

Common name Amount to Use** P.H.I.+
(trade name) (conc.) (dilute) (days)
The following materials are listed in order of usefulness in an IPM program, taking into account efficacy and impact on natural enemies and honey bees. When choosing a pesticide, also consider information relating to environmental impact.
 
A. SPINOSAD
  (Entrust)# 1.25–2.5 oz 0.31–0.6 oz 7
  (Success) 4 oz 1 oz 7
  MODE OF ACTION: A microbial (Group 5)1 insecticide.
 
B. DIAZINON* 50WP 3 lb 1 lb 21
  MODE OF ACTION: An organophosphate (Group 1B)1 insecticide.
  COMMENTS: Avoid drift and tailwater runoff into surface waters. Where cherries are grown adjacent to waterways, do not use this material.
 
 
**  For concentrate applications, use the amount given in 80–100 gal water/acre, or lower if the label allows; for dilute applications, amount is per 100 gal water to be applied in 300–400 gal water/acre, according to label.
+ Preharvest interval. Do not apply within this many days of harvest.
* Permit required from county agricultural commissioner for purchase or use.
# Acceptable for use on organically grown produce.
1 Modes of action are important in preventing the development of resistance to pesticides. Rotate chemicals with a different mode-of-action group number, and do not use products with the same mode-of-action group number more than twice per season. For example, the organophosphates have a group number of 1B; chemicals with a 1B group number should be alternated with chemicals that have a group number other than 1B. Mode of action is assigned by IRAC (Insecticide Resistance Action Committee). For additional information, see their Web site at http://www.irac-online.org/.

[Precautions]

PUBLICATION

[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Cherry
UC ANR Publication 3440
Insects and Mites
R. A. Van Steenwyk, Insect Biology, UC Berkeley
K. M. Daane, Kearney Agricultural Center, Parlier
J. A. Grant, UC Cooperative Extension, San Joaquin County

Top of page

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2006 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 How to manage pests, or in the U.S., contact your local Cooperative Extension office for assistance. /PMG/r105301911.html revised: April 18, 2006. Contact webmaster.