Check out these bugs of summer located in our forests

Check out these bugs of summer located in our forests
By Bill Cook, MSU
Extension forester/biologist

ESCANABA—Forest pests enjoy the summer growing season as much as the trees and the wildlife that rear their young.  People may notice some of these pests during vacations or, perhaps, on their own woodlands.
    Summer and the warm growing season offer plenty of food for forest plants and forest wildlife to reproduce.  Some wildlife species are a bit less desirable to many people, such as forest tent caterpillars, spruce budworms, and Lecanium scales.  
     To a forester, the outbreaks of native insects and pathogens can be an interesting part of the job.  From an ecological viewpoint, these impacts can be regenerative and fascinating.  To a backyard barbecuer, picnicker or a home landscape enthusiast, some of these events can be annoying.  
     Forest tent caterpillar (Malacosoma disstria) population eruptions occur every 10-15 years.  The FTC is among a group of “tent caterpillar” species but the FTC does not form tents, like the spring-time eastern tent caterpillar.  The FTC has a row of yellow spots in between a pair of baby-blue lines.  Aspen leaves are among the favorite food, sometimes rendering summer canopies leafless.  Mass migrations by large populations of the larvae can be dense enough to cause cars to slip off roads.  
     Spruce budworm (Choristoneura fumiferana) populations continue to erupt in various locations in the northwoods.  Also cyclical, the budworms appear for several years every couple of decades, or so.  They prefer eating the new needles on balsam fir and, secondarily, white spruce.  Multiple defoliations can lead to extensive tree death (and regeneration).  Firs grow brown in July and August, but after the killed new growth drops in the fall, the older green needles make the trees appear recovered. 

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