Pest Profile

Wheat Stem Sawfly
Cephus cinctus Norton

Pest Description

Sawflies are wasp-like insects. Adults are slender with a shiny black abdomen and yellow bands. Females have an ovipositor at the end of their abdomen, that allows them to saw into hollow-stemmed wheat to lay eggs. Larvae that develop inside wheat stems feed as they move to the base of the plant. Frass that is produced by feeding larvae forms a protective plug that provides shelter as they overwinter in stubble. The presence of the larvae causes bleaching of wheat heads, poor grain fill, stem lodging and shriveled kernals.

Source of information

R. K. D. Peterson (Montana State University), W.Morril (, G. Hein (UNL)

Pest Diagnostics


Pest photo source

R. K. D. Peterson (Montana State University)

Plant Diagnostics


Plant diagnostic image(s) source

G. Hein (UNL)