A Few Early Season Pests

Now is a great time to scout for overwintering pests in the landscape and nursery.  There is still an opportunity to apply cultural management methods to reduce pest incidence on woody plants.


(early April) Cone-like bags suspended from twigs contain overwintering females of the bagworm and each one houses 100’s of eggs that will hatch into hungry larvae as new foliage emerges.

For those of you in areas where bagworm has been found (e.g. Essex County, Northumberland County), now is the time to collect overwinter “bags”.  The overwintering bags contain adult females that will give rise to an incredible number of larvae as new foliage is emerging.


Overwintering bags on Eastern white cedar (early April)


Late May. Empty overwintering bag (eggs have hatched and migrated to new foliage) on honeylocust

The most common hosts of bagworm we’ve seen include Eastern white cedar, spruce and honeylocust but they can also be found on pine, juniper, black locust and sycamore.  Remove, collect and DESTROY bags housing the females before foliage begins to emerge this spring.  Many arborist and landscape companies offer bagworm clean up as an IPM service in early spring.

<a href="/clm/species/pyrrhalta_viburnicola"><em>Pyrrhalta viburnicola</em></a> (Viburnum Leaf Beetle) eggs on viburnum. Now is the perfect time to remove egg masses of Viburnum leaf beetle.  Look for rows of bumpy caps on the twigs of last year’s growth.  Prune out infested twigs, collect and destroy them to reduce populations of larvae on Viburnum species.

??????????????????????????????? Overwintering egg masses of Gypsy moth can also be collected and destroyed this time of year to reduce the severity of infestations of hungry larvae.  Gypsy moth eggs masses appear as brown, fuzzy, quarter-sized masses stuck to bark and other wooden objects.  They will lay their eggs on several species of deciduous trees but also have a sweet tooth for Colorado spruce.

<em><a href="/clm/species/malacosoma_americanum">Malacosoma americanum</em></a> (Eastern Tent Caterpillar) egg mass. Be sure to be on the lookout for Eastern tent caterpillar eggs masses.  Monitoring cherry, hawthorn and crabapple twigs for thickened, shiny silver bands that completely encircle small twigs.  Prune out, collect and destroy egg masses to prevent 100’s of larvae from hatching and feeding on foliage of beloved landscape specimens.



About Jen Llewellyn

OMAFRA Nursery and Landscape Specialist @onnurserycrops
This entry was posted in Insects, IPM and tagged , , , , . Bookmark the permalink.

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