We still have plenty of time for dormant season (mid Nov. – mid Jan.) insect pest monitoring in almond orchards.
What to monitor during dormant spur sampling: See here
How to do dormant spur sampling:
Use spur sampling (follow UC IPM guidelines for details)
Take 100 spurs randomly taken from ~50 trees (inside/outside/high infestation area)
Out of 100 collected, evaluate first 20 spurs (add more if needed) first and record number of spurs with/without mite eggs or live scales. Treatment threshold: ≥4 spurs with mite eggs or ≥ 4 spurs with live scales. If you have <4 out of first batch of 20 spurs, continue evaluating next 20 spurs. Further details about treatment thresholds is found toward the bottom of this sampling form
Treatment decisions based on spur sampling
Dormant oil spray is effective for:
European red mite, brown mite eggs: overwintered
San Jose scale and other scales (walnut scales): moderate population
Soft scales such as European fruit lecanium
Dormant oil + insecticide spray is effective for:
Peach twig borer (larvae overwinter inside the hibernacula on tree limbs/tree crotches)
Obliquebanded leafroller (larvae overwinter inside the hibernacula tree limbs/tree crotches)
High populations of San Jose scale
Dormant oil + insecticide spray do NOT control:
Navel orangeworm, oriental fruit moth (OFM) (overwintering in places where sprays are not effective in dormant season)
Webspining spider mites (Pacific-, twospotted-, and strawberry spider mites; they overwinter in soil and/in leaf litters on the ground)
Plant bugs including leaf-footed (overwinter in places such as structures, and other places/hosts outside of the orchard)
Consideration for safe and effective sprays (applies to all seasonal sprays)
Always use monitoring tools
Calibration of sprayer and equipment, sufficient volume of water
ALWAYS Follow the label instructions, compatibility etc.
Pay attention to weather for effective sprays (avoid rainy, foggy conditions)
Pay attention to natural enemies, bees etc.
Minimize spray drifts by shutting the sprayer off while making turns
Mixing, loading of pesticides in relatively safer places, away from water bodies