even after many days heavy raincobweb-like webs still cover tree branches throughout the Lehigh Valley, but not to be confused with early Halloween decorations.
The thick, silky webs are made by autumn webworms, a type of insect native to North America, and are common throughout the region. .
“Some people don’t like the look of giant cobwebs full of dead leaves and caterpillar poop, but don’t worry,” says Muhlenberg University professor Marten Edwards.
Edwards, head of Muhlenberg’s biology department, says the incredibly common fall webworm can be found “anywhere there’s a tree.”
Below we discuss these nests and the insects that make them in more detail.
After all, they are not worms.
“They are the larval stages of the rather elegant, fuzzy, bright white moths that appear in early summer,” Edwards said.
“Female moths lay their eggs under the leaves of trees in midsummer, and the caterpillars become visible in late summer,” Edwards explained. “Various female caterpillars congregate to build ‘tents’ or silk nests that they use for protection.
“The caterpillar feeds for four to six weeks, then spends the winter as a pupa. Moths start coming out the following summer.”
Edwards said the webworms are native to this region and much of the East Coast. However, like many invasive valley-native species, spotted lantern fly, jumping worm, emerald ash borer and the spongy moth — The web worm has spread to other regions.
“We get very upset when insects from other countries become pests in our area, but our native animals can become really nuisances when they are brought to new places where they have no natural predators. It’s good to remember that you have a gender.
“As long as the tree is overall healthy, it’s not,” said Edwards. “They feed in late summer, just before the leaves are about to fall anyway. However, they can damage some ornamental trees.”
According to Edwards, webworms feed on about 90 species of deciduous trees. They usually attack walnut, crabapple, birch and cherry trees.
“No, there are many other things to worry about,” said Edwards. “They usually stay in the web until they’ve finished eating, so they won’t bother you or your pet. Most of the time, they won’t harm the tree.”
Edwards says the methods residents use to get rid of webworms in the fall can often cause more damage to trees.
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“It’s rarely necessary to cut off a branch with a web. Unless you can easily reach it, it’s probably not worth the effort,” he said. has no value.”
And there probably won’t be any caterpillars in the nest at this time of year, Edwards said.
“Using pesticides on them is useless, not to mention a waste of money and harmful to the environment,” he said. “The webs are waterproofed, so anything sprayed on won’t reach them anyway. Autumn webworms have many unique natural insect enemies, so as we’ve seen with the spotted lanternfly, The population cannot get out of control.”
Like ladybirds, autumn webworms use a safe number strategy, Edwards said.
“They work together to put up big silk tents to protect them from the elements and predators,” he explained. “They cooperate by jerking in unison when the nest is disturbed. Thousands of synchronized wiggles must be quite alert to predators.”
“I admire how they cooperate with each other instead of seeing them as pests. Maybe we humans can learn something from them.”
To contact Morning Call reporter Molly Bilinsky: firstname.lastname@example.org.
https://www.mcall.com/news/local/mc-spt-fall-webworms-explainer-20221007-irnvzcoxsveprnsh24prwavvp4-story.html#ed=rss_www.mcall.com/arcio/rss/category/news/local/ Fall webworms are located in the Lehigh Valley.here is what you need to know