They're Asian, but they could soon be invading eastern Idaho.
Local forestry officials say they're on high alert for a foreign bug called emerald ash borer. The bug attacks and eventually kills trees.
The borer has already left a path of destruction stretching from the East Coast to Colorado.
"When it does get here, which I'm sure it will, it will be very destructive,” said Delbert Lloyd, city forester for the city of Idaho Falls.
As soon as the borer arrive, they go to work almost immediately .
"When they lay their eggs, the eggs hatch, drill into the trunk of the tree into the phloem and the cambium, which moves the water and nutrients inside the tree and starves the tree to death,” said Lloyd.
"Within a season or two seasons, it will completely kill the tree, depending on how many attack it,” he added.
You can protect your trees from emerald ash borer by injecting them with systemic insecticide.
Aaron McCracken, with Sunnyside Gardens, said it's best to use one ounce of insecticide per inch of the tree's circumference. After mixing the insecticide with water, McCracken said to pour it around the base of the tree.