They may not look threatening, but bagworms are taking a toll on local trees.
Bagworms are small, dark brown moth larvae which spin silk bags, measuring up to 2 inches, in which they live and lay eggs. Bagworms feed on the foliage of trees and shrubs, especially preferring conifers. According to the Purdue University Plant and Pest Digital Library Project, in high numbers, bagworms can severely damage trees and shrubs.
John Baker grows blue spruce and douglas fir trees in Palestine. He sells some trees for Christmas trees and landscaping. Recently, Baker said he noticed something wrong with one of the large blue spruce trees in his yard.
"I never heard of these things before, so I just thought the tree was dying," Baker said.
An inspection of his tree revealed small silk bags hanging from its branches. Baker said he then noticed the bags on several trees in his yard and called the Kosciusko County Purdue Extension. He said extension officials told him the worms were feeding on his trees.
Baker sprayed his trees with pesticide, which he said appears to be killing the bagworms. But, for the large blue spruce in his yard, he said, it might be too late."Before I could notice it, the damage was done," he said.
Baker said he has noticed bagworms in many trees in the area. He said he's even stopped in at a friend's house to warn him that he had a bagworm infestation.
"This could be a real problem down the road," Baker said. "These worms, once they pupate, the female lays up to 1,000 eggs in that bag. You're looking at one worm times 1,000."
Baker said the loss of trees could be expensive. "You're looking at $500 or $600 to replace a 5-foot blue spruce," he said.
Baker said the signs that bagworms are affecting a tree are dramatic.
"The tree will look like it was on fire," he said. "It just starts turning brown like it caught on fire and burned."
Deb Kaylor, office manager of the District 2 Forester's Office, said bagworms killed a tree in her yard last year. She said, when tree owners find bagworms in their trees, it's important to take action. At this time of year, Kaylor said, the best thing for tree owners to do is to pull the silky bags off their trees. Kaylor said the bags must be smashed or burned after being removed from the trees to ensure the worms are killed.
"In spring, if you can find a product with orthene and spray trees before the bags are formed, that will take care of the worms in the trees and the ones in the ground," Kaylor said.
