How to Manage Pests
UC Pest Management Guidelines
Cherry
Obliquebanded Leafroller
Scientific Name: Choristoneura rosaceana
(Reviewed 4/06,
updated 4/06)
In this Guideline:
|
|
|
Obliquebanded leafrollers overwinter as third instar larvae under
bud scales. The overwintered larvae pupate in spring and the first generation
of adults emerges in late March or April. Larvae are yellowish green with brown
to black heads. As they mature, larvae construct tubular shelters from a single
leaf. Adults are
reddish brown moths with dark brown bands on the wings. There are two or three
generations a year in the Central Valley; this pest is generally not found in
coastal growing areas.
Infestations of obliquebanded leafroller can occasionally reach
damaging levels in cherry. Larvae feed on flower parts and on fruit early in the
season, causing deep depressions.
Bloom time applications for other pests help keep leafroller
populations under control. However, regular monitoring each season is important
so that prompt action can be taken if damaging populations develop.
Biological Control
A number of parasites, including species of Macrocentrus, Apanteles, and Exochus, attack leafroller larvae.
General predators such as lacewings, assassin bugs, and minute pirate bugs may feed on eggs and larvae. Preservation of
natural enemy populations is an important part of keeping leafroller numbers
low. Use selective materials that are least disruptive of biological control
when treating other pests.
Organically
Acceptable Methods
Biological control and sprays of Bacillus thuringiensis and the Entrust formulation of spinosad are acceptable for use on an organically
certified crop.
Monitoring and Treatment Decisions
Although research has not been conducted in cherries, studies in almond
orchards indicate that two bloom sprays of Bacillus thuringiensis or a petal fall treatment of spinosad or methoxyfenozide (Intrepid) are more
effective at controlling this pest than a dormant treatment. Monitor and treat
orchards that had large populations of larvae the previous summer or where the
previous year's crop was infested with obliquebanded leafroller larvae.
| Common name |
Amount to Use** |
P.H.I.+ |
| (trade name) |
(conc.) |
(dilute) |
(days) |
|
| BLOOM |
| A. |
BACILLUS THURINGIENSIS ssp. KURSTAKI# |
| |
(various products) |
Label rates |
0 |
| |
MODE OF ACTION: A
microbial (Group 11.B2)1 insecticide.
|
| |
COMMENTS: Least
harmful to beneficials. Bt is a stomach poison and must be consumed by the
leafroller; therefore it is most effective when applied during warm, dry
weather when larvae are actively feeding. Most effective against young
larvae. Requires more than 1 treatment; apply second application 7–10 days after first. |
| |
| B. |
SPINOSAD |
| |
(Entrust)# |
1.71–2.5 oz |
0.43–0.6 oz |
7 |
| |
(Success) |
6–8 oz |
1.5–2 oz |
7 |
| |
MODE OF ACTION: A
microbial (Group 5)1 insecticide.
|
| |
COMMENTS: Most
effective when applied at petalfall. A fermentation-derived insect control
product that does not appear to be disruptive of most natural enemies. This
product is toxic to bees for 3 hours following treatment; apply in late
evening after bees have stopped foraging. Do not apply more than 29 oz/acre/year of Success or 9 oz/acre/year of Entrust. |
| |
| C. |
METHOXYFENOZIDE |
| |
(Intrepid) 2F |
16 fl oz |
4 fl oz |
7 |
| |
MODE OF ACTION: An
insect growth regulator (Group 18)1 insecticide.
|
| |
COMMENTS: Most
effective when applied at petalfall. Do not apply more than 16 fl
oz/acre/application or 58 fl oz/acre/season. Coverage is extremely important; sprayer speed should not exceed 2 mph. |
| |
| |
|
UC IPM Pest Management Guidelines: Cherry
UC ANR Publication 3440
Insects and Mites
R. A. Van Steenwyk, Insect Biology, UC Berkeley
K. M. Daane, Kearney Agricultural Center, Parlier
J. A. Grant, UC Cooperative Extension, San Joaquin County
Top of page
|