Clark County logo   Clark County Washington title  
Links to finding county services
Search the Web site
Clark County home page A to Z index Find it Links to other sites News releases Contact us

Environmental Services

Recycling, Garbage & Hazardous Waste

Waste Reduction

Garbage Collection & Disposal

Recycling Collection & Disposal

Recycling A-Z Index

Solid Waste Advisory Commission

Household Hazardous Waste (HHW)

Small Quantity Generators (SQG)

Yard Debris/Composting

School Programs

Naturally Beautiful





Recycle A to Z

alternatives to pesticides - bugs/pests - codling moths

                              codling moth

        Actual size:        Moth wingspan 3/4”         Larva 1”

Codling moths emerge in the spring and lay eggs that hatch into larvae that pupate during late summer and fall. Codling moth larvae are a unique white color tinged pink with a brown head. They tunnel directly to the core of fruit, usually apples or pears.

Physical control
Bands of Burlap or Corrugated Cardboard - Wrap bands of burlap or corrugated cardboard around tree trunks just after bloom, before caterpillars begin to move down the tree (late spring) and maintain them through fall. This draws larvae looking for a place to pupate. Use several thicknesses and wire or tie them on. The corrugated cardboard ridges should be 3/16” wide and face toward the tree with the ridges running vertically. Remove the bands once a week in warm weather (every two weeks in cooler weather) and kill the larvae. Continue until you have harvested all the fruit. Even in the best situations, banding will control only a small percentage of codling moths because many pupate elsewhere in the tree or drop to the ground, bypassing the trunk. Scrape away loose bark and destroy over wintering cocoons before warm spring weather.

Biological control
Pheromone Traps - Garden centers carry pheromone traps. Pheromone is a chemical substance produced by insects and animals that stimulates certain behavior of other members of the same species. Traps use female pheromones to attract males and prevent reproduction
Wasps - Trichogramma wasps and braconid wasp larvae are natural parasites of moths. These wasps are available through various mail-order companies.
Sweet Alyssum or Daisies - You can attract parasitic insects by growing sweet alyssum or daisies nearby to provide a good nectar source.
Bacillus thuringiensis (Bt) - Bt has been used with some success to help control codling moths. However, to be effective, applications must be frequent and carefully timed to reach the larvae just as they hatch. Bt is a bacteria used to control certain pest larvae, primarily caterpillars. Bt is not toxic to humans or other mammals but will kill butterfly (“friendly”) caterpillars as well as the problem ones. The bacterium kills larvae by interfering with digestion. Bt lasts on leaf surfaces five to seven days and must be ingested to be effective. There are many strains of Bt commercially available now, including strains for controlling mosquito and beetle larvae.

Least-toxic chemical control
Horticultural Oil Spray - Horticultural oils are also called summer oils; these are more highly refined than dormant oils, making them appropriate for use on leaves during the growing season.  Consult a nursery to locate a suitable product and follow all precautions. Don’t use horticultural oils when plants are flowering.
Ryania is a botanical insecticide, may be applied as eggs are laid and before they hatch. Time these sprays to coincide with moth catches in pheromone traps. Ryania is a shrub native to South America is the source of this insecticide. It incapacitates fruit moths, corn borers, codling moths and imported cabbage worms.

Back to A-Z list