Sawflies
Sawflies are members of the same insect order (Hymenoptera) that includes ants, bees, and wasps. The larval stage has a caterpillar-like body that may be brightly marked with stripes or spots.

Some species change significantly in appearance as they grow, making identification confusing. Large numbers of sawflies can strip the needles from a tree in a short period. Several species can be found on pines.

Susceptible Plants- Pines, Currents, Gooseberry.

Life Cycle- Female sawfly wasps have a saw blade-like plate to make a slit in pine needles. Their eggs are then inserted in the small openings. Upon egg hatch, the small larvae being to feed. Individual species are active at different times of the year and some have more than 1 generation.

Sawfly larvae resemble the caterpillars of moths and butterflies with a visible difference. While butterfly and moth caterpillars have 2 to 5 pairs of fleshy prolegs on the abdomen; sawflies have more than 5 pairs. This distinction can be important with regard to selecting control measures.

The biological insecticide (Bt or Bacillus thuringiensis) that works well against butterfly and moth caterpillars is not effective against sawflies. Mature larvae spin a cocoon that turns brown and resembles a bud tip. The adult will emerge from the pupal case and start the life cycle again.

Prevention and Control- Sawfly populations are usually controlled by combinations of natural enemies, predators, starvation, disease, or unfavorable weather. Outbreaks can occur when natural control does not produce high mortality. Regular inspection of pines and bushes will help to detect sawfly infestations before the larvae reach a size that can cause significant defoliation.

Since eggs are laid in clusters, feeding by groups of larvae can cause unsightly damage to ornamental or landscape plantings as well as tree nurseries. If only a small number of colonies are present and accessible, they can be handpicked, shaken off, or pruned from the tree and destroyed.

Pesticide Control-   Bon-Neem Insecticidal Soap may be effective if the insects are contacted directly by the spray. Frequent inspection of trees will allow early detection of damaging infestations.
Garlic Barrier Insect Repellent  is also an affective control for sawflies.



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