Greenstriped mapleworm

The greenstriped mapleworm is defoliating some red maples in Crow Wing County on the west side of the Mississippi River on the northern edge of Brainerd, along the southwest side of Mollie Lake north of Merrifield, and along the Legionville road bordering the southeast side of North Long Lake. By July l9th of this year, 90% of these mapleworms had grown to l and ½ inches and should be pupating in the duff within a week or two. This pest was first seen in l997 along the Legionville road, and during the next 2 years it spread to several red maple areas in Crow Wing, Cass, Morrison and other central Minnesota counties, causing heavy defoliation in many of these areas. Their numbers have dramatically fallen in Crow Wing County and their defoliation of red maples is not very noticeable. A general population collapse of this pest is predicted for most areas of central Minnesota next year. Birds and other predators and parasites reduce their numbers, and mice also feed on their dormant overwintering pupae.

Poplar-and-willow borer

Poplar and willow borer, Cryptorhynchus lapathi, is an introduced insect that has become a major pest of willow. It also attacks birch, alder and hybrid poplars across the United States and Canada. Its larvae usually feed in the lower sixteen inches of the stems of young trees by mining the bark and then boring deeper into the wood. Complete girdling kills the tree above the injury, forcing the tree to resprout, usually, resulting in multiple stems. The larvae are C-shaped and the adults are black or gray weevils with bands of pale scales on their outer wings. Just behind each adult's head is a row of two tufts of black setae (stiff and thick hairs), and a second row of three more tufts of setae is located behind the first row. Many prominent pits are present on the wings and thorax (section between head and wings).