Raspberry Horntail – Hartigia cressoni

Raspberry Horntail (Hartigia cressoni)

Latin Name: Hartigia cressoni

Common Name: Raspberry Horntail

Appearance:

  • The eggs are 1/16 inch long, curved, round, pearly white, and flattened on one end with a tip.
  • Larvae are cream to white in color, cylindrical, and have distinct segments. The head is pale brown, with a short spine at the back. Larvae develop up to 9/10 inches long and have three real legs just below the head.
  • Adults are broad-waist wasps with elongate, cylindrical bodies 1/2 to 3/4 inch long. Females are typically golden and orangish in color, with black spots. Males are predominantly black, with some yellow and orange thrown in for good measure.

Host plant: raspberry, other brambles rose.

Territory: throughout in the United States:

Damages caused by Raspberry Horntail:

Infested terminals wilt and discolor during the spring, then die back by late summer and sometimes break if not pruned off. The number of blooms and fruit may be reduced due to the infestation. Raspberry horntail does not pose a severe danger to afflicted plants’ long-term health or survival.

Description about Leaf chewers:

Insect chewing damage to plants can take numerous forms. Foliage or flowers may vanish when certain insects eat them. Occasionally, the plant will appear ragged and, upon closer inspection, will reveal bitten edges or cores. Plants can be cut at the root and topple over, or twigs can be girdled and die as a result. Mining or boring is the process of causing harm to a plant through chewing. Only the upper or lower surfaces are sometimes destroyed, producing a brown, burned look or skeletonization (openings between the veins).

Life history and Habits:

Adults emerge and mate starting in March, and the women lay eggs that hatch within several days. The immature larva feeds in a spiral beneath the surface, girdling and wilting the terminal. During the spring and summer, the larva eats and develops through four or five instars (immature stages), chewing and lengthening a tunnel in the cane. The adult larva eats its way down into the cane pith, forming a silk-lined chamber where it spends the winter as a prepupa. It pupates into an adult in late winter to early spring and bites a circular, emergence hole in the cane.

In most places, there is only one generation every year. There may be two generations every year in some areas.