The Insects of April
Conifer sawflies - Larvae feed on the older growth of pines now.
Spruce Ips - Major flights of these engraver
beetles start and can threaten at-risk spruce trees.
Cooley spruce gall - Controls are most
effective if applied before the insects make the egg sack in late April.
Zimmerman pine moth - Overwintered larvae
remain exposed on the trunk and can be controlled now.
Borers - Remove and destroy damaged tree limbs
and canes infested with borer larvae before the insects emerge.
Honeysuckle aphid - Prune out old, damaged terminals that contain eggs.
European elm bark beetle - Destroy pruned wood prior to beetle emergence.
Turfgrass mites - Seen on winter drought
stressed lawns.
Midges - Non-biting midges emerge from ponds and
mating swarms are observed over lawns.
Sod webworm / cutworm - Damage will begin this
month.
Nightcrawlers- Tunneling, cast-making and
thus lawn lumps increase with warming soils this month
Information courtesy Whitney Cranshaw, Department of Bioagricultural Sciences and Pest
Management, Colorado State University.
