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Pinyon Sawfly – Neodiprion tsugae

Pinyon Sawfly – Neodiprion tsugae Common Name: Pinyon Sawfly Latin Name: Neodiprion tsugae Appearance: The Pinyon Sawfly adult is a black or dark brown bug with legs that look like they are made of yellow. The length of it is about 6 to 8 mm. The caterpillars, or larvae, are usually green with black spots on their sides. They have several pairs of prolegs and three pairs of proper legs. Their bodies are split up into segments. Host Plants: Pine trees, especially pinyon pines (Pinus edulis), are the primary food source for the Pinyon Sawfly. Territory: Pinyon Sawflies are usually found in the western United States, especially in places where their host plants grow. Damages caused by Pinyon Sawfly:  The larvae of the Pinyon Sawfly feed on the needles of host trees. They eat the soft parts of the tips, which can cause the tree to lose its leaves and weaken. Infestations that are too bad can stop trees from growing and even kill them. Life History and Habits:  The Pinyon Sawfly goes through several steps in its life cycle:
  • Egg:The female sawfly puts her eggs on the needles of trees that it feeds on.
  • Larva:The eggs hatch into larvae, which start eating the needles to grow. As they grow, they go through several molts.
  • Pupa:Full-grown larvae usually go into the pupal stage in the ground or the soil.
  • Adult:After becoming a pupa, sawflies become adults. They mate, then the females lay eggs to start the cycle all over again.
  Pinyon Sawfly activity is highest in the warmer months, and outbreaks are most common in late spring or early summer. Pinyon Sawfly outbreaks can be controlled by cutting off branches that are highly infested, using insecticide sprays, and putting in place cultural practices that are good for tree health.