The Magic City is under siege from an Army of little creepy crawlers.

Trees are losing leaves at an alarming rate and it's all at the hands, or the mouths rather, of a little worm.

Shaun Sipma has more.

(Brian Johnson, Minot Forestry Dept.) "They can totally defoliate a tree in about a week and that's what we're seeing now."


Minot City Forester Brian Johnson says he's fielding dozens of phone calls a week because of the destruction being cause by the cankerworm.

Damage like this, leaves stripped down to the mid-rib, leaving almost an empty shell of what a tree should look like during the summer.

(Brian Johnson, Minot Forestry Dept.) "Along the river banks I've seen trees completely defoliated, Oak Park was hit really hard."


The cankerworm larva are easily recognizable.. light green stripes down the sides and a dark green stripe down the middle of the worm

But even as small as they are they can do a tremendous amount of damage.

(Brian Johnson, Minot Forestry Dept.) "Of course, it's not real good for a tree to lose all of its' leaves and totally be defoliated. But trees are extremely resilient, they will re-leaf as long as semi-hardy tree. If it happens over a course of time where you've defoliated two-three times in three years the tree's more than likely going to die."


The cankerworms feast on most hardwood trees including red and white oak, maple, elm, ash, cherry and more

Johnson says much of the canker worm larva population are fully grown now and have started to drop from tree's

He the best way now to attack the green leaf munching menace is to get ready for their return in the fall.

(Brian Johnson, Minot Forestry Dept.) "The best defense is to left them finish falling to the ground. They'll pupate under the ground and then they'll emerge as adults either in the fall or the spring. That's where tangle foot would be a good thing to put on your trees."


Tangle Foot spray can be applied at the base of a tree

Johnson says because female cankerworms are wingless they have to crawl up the tree to lay her eggs, the worm will get caught in this sticky spray and die before she can deliver the next round of worms.

(Brian Johnson, Minot Forestry Dept.) "It's the best defense, it's non evasive and it's real easy to apply anybody can do it."


It's also not toxic to humans or animals and can be purchased where most insecticides are sold

Johnson says the damage is done but a little heads up planing now can keep the canker worms at bay.

Shaun Sipma KX News. watch the video | save this article / add to your favorites list