Which insect's larvae overwinter as red-brown pupae on the ground?

The Pine Sawfly is known for its larvae that overwinter in a distinct pupal stage, which is typically red-brown and found in the soil. This life cycle strategy allows the larvae to survive through colder months by transitioning into a pupal state, where they can withstand adverse weather conditions.

Understanding this life cycle is crucial because it helps in the management and timing of control measures for this pest. Knowing that the pupae are on the ground also indicates where to focus efforts for monitoring and potential treatments in the spring when the adults emerge. The other insects listed have different overwintering strategies or life stages, which do not involve the red-brown pupal stage on the ground and thus do not accurately reflect the behavior of the Pine Sawfly.