Common Name: Obliquebanded Leafroller
Latin Name: Choristoneura rosaceana
Main Host(s): Fruit trees and bushes such as peaches, pears, apples and blueberry, as well as woody ornamentals, hawthorn, alder, roses, etc.
Obliquebanded Leafroller (OBLR) is native to and fairly widely distributed in North America. It is of greatest concern on the East Coast of the U.S. and Canada. OBLR larvae feed on a wide range of plants and trees, but preferred hosts are members of the rose family, which include peaches, pears, and apples. The pest also invades fruiting bushes such as blueberry and woody ornamentals, hawthorn, alder, and of course, roses.
There are typically two adult generations of OBLR per year. The spring flight of OBLR adults begins about three to four weeks after petal fall on apples, and continues for three to four weeks. Egg masses, containing a few hundred eggs, are laid on the upper surface of leaves. Eggs hatch after 10-12 days. The larvae feed on floral parts, developing fruits and young leaves, folding leaves for shelter. There are 6 larval stages. At pupation the larva spins a cocoon attached to the leaf.
OBLR overwinters in the third larval stage and they start feeding on floral parts and developing fruit in Spring. The first summer generation of larvae feeds on more mature fruits causing significant damage.
Impact & Damage
Injury from overwintering OBLR larvae occurs just prior to and shortly after petal fall, when the developing fruit is damaged. This Spring time feeding will lead to fruit drop or deeply scarred fruit. The summer larval generations feeds on more mature fruit with shallow surface feeding. Such feeding can have a severe economic impact on fruit quality.
To avoid problems with OBLR frequently the emphasis is on controlling the overwintering larvae, which become active with increasing temperatures. Applications of DiPel® in Spring during the bloom stages – from “tight cluster” to “petal fall” – can provide an excellent early start reducing the population. The flight of the summer adults can be monitored with pheromone traps to ensure a grower will be prepared for egg hatch of the second generation and a timely schedule of DiPel in rotation with other insecticides following IPM and insecticide resistance management.