Pine Sawfly Larvae on Mugo Pines in Rhode Island: Identification and Control

Green, Black-Spotted “Caterpillars” Eating Mugo Pines

The pests are pine sawfly larvae, not true caterpillars. Sawflies have six legs near the head; caterpillars have legs along the body.

Control Options

• Hand-pick if few colonies; drop in soapy water.
• Insecticides (active ingredient → example brand):
  acephate (Orthene), bifenthrin (Ortho Houseplant), carbaryl (Sevin), cyfluthrin (Bayer Advanced), esfenvalerate (Ortho Bug-B-Gon), imidacloprid (Bayer Tree & Shrub), permethrin (Ortho Mosquito B Gon).
• Follow label directions; spray foliage thoroughly.

Timing

Treat when larvae are small for best results. Monitor annually—sawflies can have multiple generations.