If you’ve been seeing small caterpillar looking insects on your evergreens you are not alone. Our arborists have been noticing an increase in sawflies on ornamental evergreens in the DC metro area.
Sawflies despite the name are not flies at all; they belong to the wasp family and can completely defoliate your tree or shrub in a few short days. Although Sawfly larvae feed on a wide range of trees our Arborists out in the field suggest keeping a close eye on your Spruces, Cedars, and Pine trees since these species are most susceptible in our area.
How Sawflies Damage Your Trees:
The adult sawfly resembles a wasp but does not eat or sting. The sawfly larva is actually what feeds on trees and plants causing damage. Larvae tend to look like caterpillars with three large legs and seven smaller false legs. Although they may appear individually they are typically seen in groups that feed on the leaves and needles of plant life. If Sawfly infestations are left untreated they will rapidly defoliate many species of trees (note the complete absence of needles on portions of the plant in the picture above). Early intervention is key to keep your trees and shrubs from becoming Sawfly victims. Keep an eye out for the warning signs below.
SIGNS & SYMPTOMS:
- Holes or papery spots along leaf midribs
- Skeletonized leaves
- Needles may appear brown and wilted
- Complete defoliation or sparse, patchy, missing foliage
- Caterpillar looking larvae on your trees and shrubs (typically in clusters)
- Stunted tree growth
- Shoot death
- Young larvae are often visible, appearing as a caterpillar in large groups
How Can I Get Rid Of Sawflies?
A number of treatments and techniques can be employed to rid trees and shrubs of Sawflies; however, they must be administered correctly so that they rid the tree of the infestation without damaging its health.
Traditional Treatments: Sawflies are generally controlled using systemic treatments and foliage sprays of insecticides. The type of treatment will depend on the time of year and what stage the insect is in (Egg, Larvae, Adult, etc). At small population levels, you can manually remove the sawflies to help gain control of the infestation.
Organic Control Through Beneficial Insects:
Sawflies have many natural enemies including, predatory beetles, parasitic wasp, and ladybugs. We can release these predators on your property in order to control the population of this insect. This is a great option for homeowners that are worried about chemicals on their property or have kids that would love to be involved in releasing the bugs on the property.
Prevention: If you’ve had sawfly problems in the past it’s best to invest in a Canopy Protection Plan. This plan will be able to catch sawfly larvae when they are at their most vulnerable, early in their life cycle before they do damage to your tree. If your trees are healthy and have been maintenance regularly they are less likely to be severely damaged by sawflies. Keeping them healthy year round will help them recover from Sawfly damage.
Book online or call our office to schedule an Arborist consultation to make sure your trees/shrubs aren’t sawfly victims.