How to Manage Pests
UC Pest Management Guidelines
In this Guideline:
Pheromone traps are used to monitor the flights of certain pest
moths and San Jose scale. Use pheromone traps to monitor San Jose scale,
omnivorous leafroller, codling moth, and peach twig borer in all orchards. Only
orchards that did not receive a dormant or bloom treatment require peach twig
pheromone traps. Codling moth traps are needed only in those few orchards with
a history of codling moth infestations.
The information obtained from trap catches can be used to
schedule control actions when used in conjunction with degree-day calculations.
The traps are used to establish a biofix—an identifiable point in the
life cycle of the pest at which you can begin degree-day accumulation or take a
management action. For example, the biofix for peach twig borer is the date
that the first adult moth of each generation is caught.
FOR USING PHEROMONE TRAPS
traps in each orchard for which you need to make pest management decisions.
should be placed in orchards by the dates indicated in the table below.
- Use at least 2 traps per block for moths, and 3 or 4 per
block for San Jose scale.
- Distribute the traps uniformly throughout the orchard and
use the same locations each year.
- Place additional traps in hot spots.
- Hang traps 6 to 8 feet high, 1 to 3 feet inside the canopy
in the north quadrant of the tree, in the shade, and at least 5 trees in from
the edge of the orchard.
- Check traps twice a week until the biofix is established;
thereafter, check traps weekly.
- Remove trapped insects from the trap bottom after you count
and record the trap catch on a monitoring form .
- Replace trap bottoms monthly or when they become covered
- Follow manufacturer's recommendations for replacing
- Store pheromone dispenser in a refrigerator or freezer.
WHEN TO PUT OUT TRAPS
||Trap placement date
|San Jose scale
||Determine biofix; excellent for monitoring beneficials.
(San Joaquin Valley)
||Determine biofix to begin degree-day
accumulation to predict onset of second flight.
||Soon after bud break or
by March 15
||To help detect first moth emergence and set biofix for degree-day accumulation to predict egg hatch.
||March 20 (San Joaquin Valley)
April 1 (Sacramento Valley)
||Determine biofix for each generation; use degree-days to determine caterpillar monitoring schedule.
UC IPM Pest Management Guidelines: Plum
UC ANR Publication 3462
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