Porcupines are mammals. They are vegetarians. Many people consider porcupines to be a nuisance because of the damage they cause to trees and wooden structures. In addition to plant material, porcupines crave salt and are attracted to objects that have salty human sweat on them, such as ax handles, boat oars, etc.

porcupine in tree
Porcupines average 13 to 20 pounds. Adults have up to 39,000 quills. They make a wide variety of sounds from whimpers to screams.

porcupine closeup
Porcupines are nocturnal. They spend a lot of time in the tops of trees.

bark damage on tree
During the winter porcupines damage trees by chewing through the bark to eat the inner bark. They prefer softwood trees. They rarely kill trees.

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Identification and Control Information

[Photos, left to right: Joseph O'Brien, USDA Forest Service, Bugwood.org; Paul Bolstad, University of Minnesota, Bugwood.org; Steve Webb, Bugwood.org; Joseph O'Brien, USDA Forest Service, Bugwood.org]