Insects » Mint Stem Borer
     
 
 


Mint stem borer adult (bottom) and larva in stem (top)

Mint Stem Borer
Pseudobaris nigrina (Say)

Adults are small, black, snout-nosed beetles about 2 mm long. Larvae are about 3 to 5 mm long, slender, white, legless, and have a brown head capsule. Adults feed on leaves, and larvae burrow inside the stems of the mint plant just above the soil line. Occasionally they bore into the below-ground rhizomes. Host plants: mint, kochia, goldenrod.