In this Issue
- Codling moth: updated spray dates table
- San Jose scale: treatment time coming up
- Coryneum blight: apply a curative fungicide after the rain
- Peach twig borer: updated spray dates table
- Obliquebanded leafroller: treatment date coming up (tart cherry)
POME FRUITS
Codling Moth
View a pdf of the spray timing table. Be sure to read the instructions at the top of the page, for how to read the table.
Several growers using mating disruption have reported worrisome high trap catches, especially using the CM-DA Combo lure. In some areas, the codling moth populations appear to have been steadily increasing over several years.
Entomologist, Diane Alston suggests that the high catch is partially due to a slow moth emergence at the beginning of the generation because of the cool weather. Now with the recent hot temperatures, the emergence curve is ramping up, with a majority of the moths flying over a very short period.
It is very important to apply cover sprays in a timely manner, and to add more applications if needed, based on trap thresholds.
Options for commercial growers.
Keep in mind that several products (Delegate, Altacor) only target eggs and larvae, not adults. So trap catches may not decline rapidly after their application.
San Jose Scale
If your trees have SJS and you applied a dormant oil spray, note that most overwintering adults will have survived that spray. Therefore, a treatment targeting crawlers will need to be applied.
Treatment timing windows:
- Cache and northern Box Elder counties, and high elevation areas: June 23 – 29
- Warmer Wasatch Front locations: June 15 – 20
- Cooler Wasatch Front locations: June 18 – 24
- Carbon and Iron counties: June 18 – 24
- Washington (New Harmony; not St. George): June 14 – 18
Options for commercial growers.
STONE FRUITS
Coryneum Blight
As soon as possible, apply a curative fungicide after the rains to prevent further infections. These include Adament, Pristine, Quilt, Abound, and Gem.
Peach Twig Borer
View a pdf of the spray timing table. Be sure to read the instructions at the top of the page, for how to read the table.
The first peach twig borer sprays should be on this week in the Wasatch Front area, and in later weeks in cooler areas.
Options for commercial growers.
Obliquebanded Leafroller
The Utah IPM Program has leafroller monitoring traps in several orchards across northern Utah. We set a biofix of June 5 for most Utah County locations.
This insect is mostly an issue as a contaminant during tart cherry harvest.
Treatment Options to Target Newly Hatched Larvae
- Altacor, Bt, Delegate, Intrepid, pyrethroids, Success/Entrust, Voliam Xpress
- Apply once (twice in high population or problem areas) starting on June 24-25