Extension > Garden > Diagnose a problem > What insect is this? > Trees and shrubs > Caterpillars, maggots, grubs, and similar immature insects - Under 1 inch long > Mountain ash sawfly
Mountain ash sawfly
Pristiphora geniculata
E. Bradford Walker, bugwood.org
Description: 1/2 - 3/4 inch long. Orange brown head, light green in color.
Where/When: Black or orange head with black spots over a yellow-green body.
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