Codling Moth: Control in Home Plantings
Codling moth is an important insect pest of apples and pears in North America. The cream-colored larvae of this moth tunnel into fruit.
Order: Lepidoptera
Family: Tortricidae
Description and Lifecycle
The adult codling moth is a small moth, approximately ½ inch in length. The moths are gray with narrow alternating bands of white and have coppery wing tips. The adult moth is rarely seen since it is active at night. The larvae, usually found in fruit, are creamy white to slightly pink. The head and first segment after the head are black. The codling moth overwinters as a full-grown caterpillar within a cocoon, pupating in winter or early spring, typically within days of apple bloom. Mating occurs within a few days of adult emergence, followed by egg laying thereafter. Eggs are deposited singly on leaves; each egg is about the size of a pin head. The number of eggs laid per female ranges from 30 to 70. The eggs will hatch in six to 14 days, depending on temperature. Within 24 hours of hatching, the larvae bury into the fruit. As the caterpillars grow, they molt five times, going through five larval stages before they are full-grown. Once full grown, the larva emerges and seeks a protected site to spin a cocoon. Sites are typically beneath bark or underneath debris around the base of the tree. A second, and sometimes third, generation can be produced in a single summer.
Phil Sloderbeck, Kansas State University, Bugwood.org
Codling moth larvae.
Whitney Cranshaw, Colorado State University, Bugwood.org
Codling moth pupa.
Scott Bauer, USDA Agricultural Research Service, Bugwood.org.
Adult codling moth.
Whitney Cranshaw, Colorado State University, Bugwood.org
Codling moth injury.
Quick Facts
- The caterpillar of the codling moth is cream-colored, and most injuries are usually produced by the second-generation larvae during early summer
- Non-chemical controls that can reduce fruit injury include fruit thinning, prompt removal of infested fruit, bagging of fruit and the use of certain traps
- Insecticides are useful when applied to coincide with periods when eggs are being laid and before the newly hatched caterpillars bore into fruit
- Pheromone traps can be useful in timing sprays
Codling Moth Injury
Caterpillars tunnel through the flesh of apples, often attacking areas that provide some cover, such as the end, calyx, stem end, or where two fruit touch. Codling moths can also infect pears and are rarely found in cherries, peaches, and large-fruit crab apples. Although caterpillars’ tunnel through the fruit flesh, most of the feeding is on developing seeds in the core. When the caterpillars are fully grown, they tunnel out of the fruit, creating larger wounds and leaving behind piles of brown excrement.
Management
Biological Control
- There are many natural controls of codling moth: some parasitic wasps and a host of generalist predators (e.g., assassin bugs, minute pirate bugs, green lacewing larvae). These predators provide important supplemental control on unsprayed trees or trees where insecticides are selective in their effects
- Trichogramma wasps have a great biological control potential
- Due to the serious nature of codling moth injury, where a single larvae can destroy a fruit, natural enemies often will not provide effective control
Cultural Control
- Thinning fruit that are in contact, also makes good spray coverage possible
- Removal of infested fruit
- Removing debris from vicinity of the base of the tree
- Removing flaps of bark on older trees
- Banding tree trunks with cardboard or burlap bands can provide sites where codling moth will pupate. They can then be collected and destroyed
- Individual fruit can be enclosed in a small paper bag to exclude codling moth
- There are no apples or pears that are completely resistant to codling moth, although firmer fruits are somewhat less susceptible
Trapping and Monitoring
- Several traps can be used in management of codling moth. Some are helpful in detecting when moths are active, which allows for more targeted use of pesticides
- Pheromone traps only attract males, but can be used for scouting
- The spring emergence of codling moths can be easily monitored using the use of pheromone traps.
Chemical Control
There are limited numbers of insecticides on the home/garden consumer market available for managing codling moth in home orchards. All require repeated application, timed for periods when eggs are being laid and hatching, and thorough coverage of fruit.
CSU Extension Fact Sheet
Download or view the CSU Extension’s PDF fact sheet for your reference.