Colorado July Insect Checklist

//Colorado July Insect Checklist

Colorado July Insect Checklist

CHECKLIST OF COMMON INSECT RELATED EVENTS
– Metro Denver/Boulder Area

This is a generalized checklist of when some of the more important insect related events tend to occur in the Central, South and East Counties areas. Year to year variations are considerable and this should only be used as a guideline to anticipate and help recognize common insect occurrences.

Early July

Household Insects

Strawberry root weevils: Migrations into homes accelerates.
Sun spiders (wind scorpions): Peak period of indoor migrations.

Tree/Shrub Insects

Peach tree borer: Egg laying typically begins. Preventive sprays should be made at this time to kill newly hatching larvae.
Elm leaf beetle: First generation larvae become full-grown and move down trunk to pupate.
Black vine weevil: Adult leaf notching injuries are obvious on euonymus and rhododendron.
Leafcurling aphids: Most species have departed from overwintering host trees and shrubs.
Cooley spruce gall adelgids: Peak period of emergence from galls and migration to Douglas-fir alternate host.
Pinyon pitch mass borer: Adult emergence continues and egg laying begins.
Codling moth: Flights and egg laying of the second, most damaging, generation ofte n begin at this time.
Leafcutter bees: Characteristic cut leaf injury begins to appear on rose, lilac and other susceptible hosts.
Apple maggot: Expect the emergence of adult flies and onset of egg laying. Monitor flights with sticky traps.

Garden Insects

Mexican bean beetle: Larvae begin to damage beans.
Colorado potato beetle: Peak period of larval injury. End of first generation.
Tobacco budworm: Early evidence of injury to flowers may be present.

Lawns

Sod webworms: Watch for damage to turf grasses by the second generation larvae.

Miscellaneous

Honey bee swarms: This is commonly a time for peaks in swarming in sunny afternoons.

Late July

Tree/Shrub Insects

Codling moth: Second generation continues to lay eggs. Monitor flights with pheromone traps.
Elm leaf beetle: Second generation egg laying and hatch often occurs in late July.
Cooley spruce gall: Abandoned galls become dry and very conspicuous.
Pearslug: Larvae damage plum, cotoneaster.
Elm aphids: Stages on leaves excrete large amounts of honeydew.

Garden Insects

Tomato hornworms: Peak damage by larvae occurs over the next month.
Potato/tomato psyllid: Symptoms may begin to appear on potatoes and tomatoes.
Mexican bean beetle: Larvae begin to damage beans.

 


SEASONAL CHECKLIST OF SOME COMMON INSECT RELATED EVENTS – ARAPAHOE/DOUGLAS/ELBERT COUNTIES

Concerned about your lawn or tree health?
Call us at 303-806-TREE or click here to schedule your free plant health care consultation now!

Early July

Household Insects

Strawberry root weevils: Migrations into homes accelerates.
Sunspiders/Windscorpions: Migrations into homes often peaks around this time.

Tree/Shrub Insects

Peach tree borer: Egg laying typically begins. Preventive sprays should be made at this time to kill newly hatching larvae.
Elm leaf beetle: First generation larvae become full-grown and move down trunk to pupate.
Black vine weevil: Adult leaf notching injuries are obvious on euonymus and rhododendron.
Leafcurling aphids: Most species have departed from overwintering host trees and shrubs.
Douglas-fir tussock moth: Typical peak period of injury. Monitor infested trees.
Cooley spruce gall adelgids: Peak period of emergence from galls and migration to Douglas-fir alternate host.
Pinyon pitch mass borer: Adult emergence continues and egg laying begins.
Mountain pine beetle: Adult emergence usually begins.
Leafcutter bees: Characteristic cut leaf injury begins to appear on rose, lilac and other susceptible hosts.

Garden Insects

Mexican bean beetle: Larvae begin to damage beans.
Tobacco budworm: Early evidence of injury to flowers may be present.
Grasshoppers: Egg egg largely completed. Optimum time for treatment.

Lawns

Sod webworms: Watch for damage to turf grasses by the second generation larvae.
Ant swarms: Winged ants are forced out of colonies during warm afternoons following rainfall events

Late July

Tree/Shrub Insects

Codling moth: Second, and most damaging, generation begins to lay eggs.
Elm leaf beetle: Second generation egg laying and hatch often occurs in late July.
Sawflies: Neodiprion autumnalis may cause damage peak in midsummer.
Cooley spruce gall: Abandoned galls become dry and very conspicuous.
Pearslug: Larvae damage plum, cotoneaster.
Elm aphids: Stages on leaves excrete large amounts of honeydew.

Garden Insects

Tomato hornworms: Peak damage by larvae occurs over the next month.
Potato/tomato psyllid: Symptoms may begin to appear on potatoes and tomatoes.
Grasshoppers: Damage accelerates over the next month.
Mexican bean beetle: Larvae begin to damage beans.
European paper wasp: Colonies start to increase greatly in size and foraging adults are commonly seen.

 


Concerned about your lawn or tree health?
Call us at 303-806-TREE or click here to schedule your free plant health care consultation now!

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See more Summer Plant Health Care articles here.

 

last updated

Aug 20, 2019 @ 12:24 pm

 

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2019-08-20T12:24:46-06:00