Forest tent caterpillars have invaded some trees in Steinbach.

"It's about every seven years we may see them come through and this happens to be that year for us," notes Dorinda Penner, owner of Sunshine Greenhouse.

Penner suggests one of two ways to get rid of them. The first, involves removing the clusters, placing them in a bag and then tying that bag tight in order to suffocate the caterpillars. The other option is to apply a biological insecticide called BTK.

Penner says BTK can be purchased at any garden centre. The spray is applied to the foliage, not the insects. Then, as the caterpillars feed off the leaves, they will start to fall off the tree and die. Penner says this could be two to three days after BTK is applied. She adds this insecticide will not harm any other insects.

According to Penner, forest tent caterpillars like to feast on Ash trees, Poplar trees and even fruit trees. She notes the season should last one to two weeks in Steinbach before the insects begin to cocoon for the following year.

Though forest tent caterpillars can limit a tree's growth for that year, Penner says no tree should die as a result.

"They move through our forested areas without any treatment and we don't see loss of trees, we just see significant setback," says Penner. "Spraying the BTK, is going to keep your tree healthier, there's no question about it and it's going to stop it from going through and feeding off of other trees."

Penner says BTK is totally safe. She adds you do not need to wear a mask or use fancy gloves while applying it.

"It's completely biological and safe and it works," says Penner.

Meanwhile, Russ Dyck of Steinbach Parks and Recreation says historically the city does not spray for forest tent caterpillars unless it becomes a major infestation.