Spring brings invasion of eastern tent caterpillars

NORTHEAST PHILADELPHIA (WPVI) -- From the city to the suburbs, caterpillars seem to be invading neighborhoods.

It does appear that there are more mysterious silk tents on trees this spring in comparison to last year. But experts say it's all a part of nature' cycle.

The pods appear annually in trees all over the eastern United States, and they're all over Pennypack Woods as they are every spring.

They are the tents of the eastern tent caterpillar, and they have some local folks out freaking out.

Mary Henriques says, "They're creepy crawlers, and they make a lot of dirt and mess, and they've been here for years."

But they're nothing to fear, nature experts say.

Mark Fallon of the Briar Bush Nature Center explains, "They make these tents to protect themselves - from predators, from the elements, from cold temperatures. They hide in there."

The eastern tent caterpillar eventually evolves to become a moth, and this is the height of the hatching season. They're only real crime is eating leaves on trees - mostly wild cherry and other trees that promptly rejuvenate.

Fallon tells us, "These are really not a dangerous insect. They're not extremely destructive. They rarely kill the trees that they're eating. And they're incredibly important to birds."

Since this is the caterpillar's hatching season, they are crawling all over many neighborhoods in their evolution to moth.

If they annoy you, pick them up with a stick and throw them in a bucket of water.

"Spraying them is actually very ineffective. Getting those chemicals in your yard is not good for you and it really does very little," Fallon said.

One thing's for sure, and that's that these silken tents will be back again next year when spring comes around again.