Corvallis MT - COVM
Data is up through August 28, 2026
Growing Degree Days since January 1:
Change Station:
Apple Maggot
Biofix: January 1, 2026
Degree Days since Biofix:2671
Management Action 1 Week Ago:none
Present Management Action:none
Management Action for the Next 3 Weeks:none
For a current Apple Maggot summary click here.
Billbugs
Biofix: January 13, 2026
Degree Days since Biofix:3704
Management Action 1 Week Ago:none
Present Management Action:none
Management Action for the Next 3 Weeks:none
For a current Billbugs summary click here.
Cereal Leaf Beetle
Biofix: May 6, 2026
Degree Days since Biofix:2218
Management Action 1 Week Ago:none
Present Management Action:none
Management Action for the Next 3 Weeks:none
For a current Cereal Leaf Beetle summary click here.
Codling Moth - Trap Biofix
Biofix: May 10, 2026
Degree Days since Biofix:1600
Moth Flight: 85% of moths in 2nd generation have emerged
Egg Hatch: 53% of moths in 2nd generation have hatched.
Management Action 1 Week Ago:none
Present Management Action:September 3 - Second Generation, end of peak egg hatch.

Egg hatch is waning for the second generation, and will be completely over by 2100 degree days.
Management Action for the Next 3 Weeks:September 3 to September 7 - Second Generation, end of peak egg hatch.

Egg hatch is waning for the second generation, and will be completely over by 2100 degree days.
For a current Codling Moth - Trap Biofix summary click here.
Fire Blight
*This model only applies when trees are in bloom.
Greater Peachtree Borer
Biofix: January 1, 2026
Degree Days since Biofix:1643
Management Action 1 Week Ago:none
Present Management Action:none
Management Action for the Next 3 Weeks:none
For a current Greater Peachtree Borer summary click here.
Obliquebanded Leafroller
Biofix: June 21, 2026
Degree Days since Biofix:1247
Management Action 1 Week Ago:August 19 to August 21 - Second generation moth flight begins.

August 24 to August 25 - Most larvae of the first generation are mature.
Present Management Action:September 3 - Larval feeding of the first generation ends (most are now in the pupal stage).
Management Action for the Next 3 Weeks:September 3 to September 4 - Larval feeding of the first generation ends (most are now in the pupal stage).

September 16 to September 19 - Second generation egg hatch begins; apply treatment now if necessary.
For a current Obliquebanded Leafroller summary click here.
Peach Twig Borer
Biofix: June 4, 2026
Degree Days since Biofix:1397
Moth Flight: 87.4% of moths in 2nd generation have emerged
Egg Hatch: 36.3% of moths in 2nd generation have hatched.
Management Action 1 Week Ago:August 19 to August 22 - Begin sprays for second summer generation. Choose a later date in this time span if damage was light in your orchard last year. These dates correspond to 5% - 16% egg hatch.
Present Management Action:none
Management Action for the Next 3 Weeks:none
For a current Peach Twig Borer summary click here.
San Jose Scale
Biofix: May 10, 2026
Degree Days since Biofix:1515
Males: Adult Males is over for the season
Crawlers: 33.8% of crawlers in 1st generation have emerged.
Management Action 1 Week Ago:none
Present Management Action:August 30 to September 3 - Second generation crawlers are most active now. If you have a heavy infestation, treat at this time with Esteem or 1% horticultural oil.  Otherwise, wait and spray with oil next spring at budbreak.
Management Action for the Next 3 Weeks:September 3 to September 9 - Second generation crawlers are most active now. If you have a heavy infestation, treat at this time with Esteem or 1% horticultural oil.  Otherwise, wait and spray with oil next spring at budbreak.
For a current San Jose Scale summary click here.
Spotted Wing Drosophila
Biofix: January 1, 2026
Degree Days since Biofix:1853
Management Action 1 Week Ago:August 21 to August 22 - Continue servicing traps. Adult emergence of the 3rd generation of flies is peaking at this time.
Present Management Action:none
Management Action for the Next 3 Weeks:September 7 to September 9 - Continue to keep fruit protected with insecticides if spotted wing has been confirmed on your fruit farm.

Peak egg-laying by 3rd generation flies is now occurring.
For a current Spotted Wing Drosophila summary click here.
Walnut Husk Fly
Biofix: January 1, 2026
Degree Days since Biofix:3129
Management Action 1 Week Ago:none
Present Management Action:August 28 - 50% of adults have emerged.
Management Action for the Next 3 Weeks:September 11 to September 12 - 90% of adults have emerged.

September 15 - Larvae begin exiting the host fruits or nuts to drop to the ground to pupate.
For a current Walnut Husk Fly summary click here.
Western Cherry Fruit Fly
Biofix: Not established yet for 2026
Degree Days since March:3129
Management Action 1 Week Ago:none
Present Management Action:none
Management Action for the Next 3 Weeks:none
For a current Western Cherry Fruit Fly summary click here.