WSU Tree Fruit Research & Extension Center

Tree Fruit Market Diseases

Thursday, November 23, 2017

WSU-TFREC/Postharvest Information Network/Tree Fruit Market Diseases/leafroller



Harvested apples are often found with large depressed areas of russeted and corky tissues, or with slightly raised or undulating spots. These symptoms may be accompanied by distortion of the fruits. They result from the feeding of certain chewing insects early in the season when the fruits are small. The exact identity of the insect concerned cannot be determined after the injury has healed. Among the insects causing this type of injury are the fruit tree leaf roller (Archips argyrospilus Walker), the green fruitworm (Lithophane antennata Walker) and related species, and the larva of the rusty tussock moth (Orgyia antiqua L.).

The larvae of the red-banded leaf roller (Argyrotaenia velutinana Walker) consume areas of skin and outer flesh that may be extensive on some fruits. The area where feeding occurs is usually in touch with another fruit or is covered by a leaf or by a silken web. This insect species became a serious pest after the widespread use of DDT as an orchard spray in the late 1940s. It is usually most abundant late in the season. As a result the late injured areas do not heal, but offer a favorable opportunity for the entrance of various rot organisms.

The State agricultural experiment station or extension service can provide recommendations for best control of these insect pests.

Leaf roller damage, Golden Delicious
Leaf roller damage, Golden Delicious

Leaf roller damage, Elstar
Leaf roller damage, Elstar

Leaf roller damage, Elstar
Leaf roller damage, Elstar

Leaf roller damage, Elstar
Leaf roller damage, Elstar

Tree Fruit Research & Extension Center, 1100 N Western Ave, Washington State University, Wenatchee WA 98801, 509-663-8181, Contact Us