Just as trees begin to leaf out in the spring season, spongy moth caterpillars (formerly gypsy moth) are hard at work, eating those brand-new leaves.
As spongy moths strip trees of their leaves, trees become weak and susceptible to other injuries.
When it comes to tree pests, the best thing we can do is learn more, then take proactive steps to control them. Here are all the gypsy moth facts you need!
Originally from Europe and Asia, spongy moths made their debut in the U.S. more than a century ago. In the late 1860s, Leopold Trouvelot transported a trove of moths to his Boston home.
Soon after, the first spongy moth outbreak was around 1890.
As the birthplace of the U.S. spongy moth outbreak, Massachusetts trees are especially affected by the insects.
The good news is that the moths are slowing down this year. The University of Massachusetts reported that nearly 90 percent of spongy moths died last year. The rain in 2017 activated a native soil fungus that reduces the spongy moth population.
But that doesn’t mean spongy moths are gone for good. Defoliation is expected in Essex, Hampden, Hampshire, Norfolk, and Worcester Counties. But, Massachusetts trees won't experience the extreme rate of leaf loss they have in past years.
Spongy moths go through four stages.
Spongy moth caterpillars partially or entirely strip trees of their leaves. They prefer oaks, especially white and chestnut. But they’ll also eat alder, aspen, basswood, birch, hawthorn and willow trees.
Then, because the tree is weak from the loss of its leaves, it becomes vulnerable to other problems.
“Like people, when [trees] get weak, they’re more susceptible to certain pests and diseases. The year of the drought, we lost a lot of trees or they were under stress," said the manager of Hartney Greymont, a Davey company in this Wicked Local Dedham story.
The best advice? Be proactive. Here’s what to do: