An important factor to consider when assessing the potential impact
of a grasshopper infestation is the species composition of the grasshopper
population. Most species of grasshoppers are inocuous, and at least one
species is considered beneficial. Therefore it is important to know if
a grasshopper population is primarily comprised of pest species. A list
of the 15 most important grasshopper pest species was assembled*, and then
divided into two groups: the "Dirty Dozen" pests of rangeland, and the
"Fearsome Five" pests of croplands and disturbed areas (two of the fifteen
species appear on both lists). To access the lists, you will simply have
to make a couple decisions based on where the grasshoppers were collected
and their developmental stage.
*The list is based on the expertise of grasshopper researchers at the University of Wyoming and information in the 1996 USDA Grasshopper Integrated Pest Management User Handbook. The emphasis of this list is on pest species of the western Great Plains and the Rocky Mountain region. As with any list of this type, there will be inclusions/exclusions that are debateable.