Letter: Webworms are important bird food

To the Editors:

I am writing on behalf of the Wilton Pollinator Pathway project and the Norwalk River Watershed Association in response to your article Webworms invade Wilton from Sept. 6, 2018. We at the Pollinator Pathway are working to protect bees, birds, and butterflies by offering alternatives to pesticides, which harm pollinators as well as the pests they target. The two pesticides recommended in the article are “definitely toxic to pollinators,” according to Kimberly Stoner, and entomologist specializing in native bees and pollination at the CT Agricultural Experiment Station.

Webworms are native to our area and are a food source for birds, according to the Massachusetts Audubon Society. They are also part of the food chain for beneficial insects that help keep other pests at bay. Rarely do webworms do lasting damage to trees. “Fall webworms can defoliate entire trees, but unless a tree has been stressed by other factors, it usually recovers, and the main negative effects of an infestation are aesthetic. Numbers and locations of webworm outbreaks differ from year-to-year based on environmental factors, so the same trees are not necessarily affected each year,” reports Mass Audubon.

The problem is one of aesthetics, and Audubon offers a solution: “Remove the webs when they first appear in July, using a long stick or pole. If you wait until the caterpillars are larger and more abundant, opening the webs can provide an additional food source for nesting birds.”

Mary Ellen Lemay of the Hudson to Housatonic Conservation Initiative told the Pollinator Pathway that she tried this recently in her yard in Trumbull, “I poked a hole in the webs, and cardinals swooped in to eat the caterpillars.”

Audubon advises that burning the webs “will do more damage to the trees than the caterpillars will, and chemical and biological treatments also have downsides disproportionate to the problem.” Those downsides include harming water quality and threatening our pollinators.

Interestingly, the webs attract a great variety of parasitic wasps and flies, which use the caterpillars as hosts. “These so-called ‘parasitoid’ insects are key natural allies in controlling populations of pest species, and webworm colonies arguably perform a service by providing communal nurseries for these species,” reports Audubon.

For more alternatives to pesticides, check our website Pollinator-Pathway.org

Louise Washer

President, Norwalk River Watershed Association

Co-founder Wilton Pollinator Pathway

Wilton, Sept. 11