Information from Dr. Vince Jones, Dr. Ute Chambers, WSU Entomology; and Dr. Jay Brunner, WSU Emeritus. Summarized by Tianna DuPont, WSU Extension. March 2017. Updated April 2019.
Mating disruption dispensers should be in place before the start of bloom.

Mating disruption floods the orchard with synthetic pheromone, making it harder for the males to find females. The delay in mating of females reduces egg production and the length of the period females can lay eggs. Mating disruption works best when it is hot because the delay in mating operates on a heat-unit (degree-day) basis. Hotter weather means the delay in mating is greater (so total eggs laid are reduced) and the females age faster, both factors reduce the growth and size of the population.
Although mating disruption is not a stand-alone treatment, it makes all other treatments work better. For example, Dr. Vince Jones, WSU Entomology simulated the effects of a series of management strategies on control efficacy. You can see that all the programs with mating disruption (blue bars) perform much better than the programs without mating disruption (grey bars). For additional examples, see “What Makes an Effective Codling Moth Management Program” on the Decision Aid System (DAS) site.
Additional Information
What Makes an Effective Codling Moth Management Program?
How Does Codling Moth Mating Disruption Work?
Contacts
Vincent P. Jones, Professor & Entomologist
Department of Entomology, Washington State University
Tree Fruit Research & Extension Center, Wenatchee, WA
vpjones@wsu.edu
Ute Chambers, DAS Manager/ Outreach
Department of Entomology, Washington State University
Tree Fruit Research & Extension Center, Wenatchee, WA
uchambers@wsu.edu
Tianna DuPont, WSU Tree Fruit Extension Specialist
Tree Fruit Research & Extension Center, Wenatchee, WA
tianna.dupont@wsu.edu, (509) 663-8181