Sawfly Control: How to Get Rid of Sawflies

This article is a general sawfly control guide. Follow the recommended steps and products listed in this DIY guide, and we guarantee 100% control of adult and larvae stage of sawflies within your yard.

Despite their name, sawflies are members of the Hymenoptera with bees and wasps. Unlike wasps, sawflies do not posses a stinger. These two-winged pests attained their name from the saw-like ovipositor attached to the end of its abdomen which helps them to cut into the tissue of plant leaves to insert eggs. Prevalent across the United States these pests fall into numerous species such as the red-headed pine sawfly, oak sawfly, rose sawfly, grass sawfly, conifer sawfly and so forth.

While there are many different types of sawflies one thing each species will share is the amount of damage inflicted to ornamentals, trees, and shrubs residing in your property. Many homeowners often mistake this pest for common moth or butterfly caterpillars during its larval stage. Unfortunately, this leads some gardeners or homeowners to encourage this supposed caterpillar growth leading to increased foliage damages and increase of infestation.

Though a heavy amount of damage surrounds the sawfly species it is it their larvae that feed on plant leaves and grass, while the adult feeds on pollen and nectar. Follow our DIY treatment guide below to learn more about this pest and how to completely remove them from your yard by using the recommended steps and products.

Identification

Before proceeding with treatment, you will need to be certain that the insect invading your property is a species of sawfly. Misidentification can lead you to using the wrong insecticides, which can be a waste of your finances and time. While sawfly species will vary in some of their features they will share a few distinguishing characteristics.

• There are thousands of different species of sawflies, and they each have a unique appearance from when they hatch as larvae to when they pupate into adults. Though each species will vary they can be distinguished by the plant they are infesting. These pests are plant specific and will not move to another species of foliage. For example, a dogwood tree inhibiting signs of damage may be infested with the dogwood sawfly. If you are experiencing multiple signs of damages to different species of trees and shrubs then it could be several species of sawflies in your yard.
• Unlike other female wasp species, all sawflies lack stingers. Only the female sawfly will possess a saw-like apparatus known as the ovipositor at the tip of its abdomen, which it uses to cut into the leaf or stem tissue of plants to allow for the insertion of eggs.
• As adults, they look like flies or wasps, but upon closer examination it will reveal that sawflies have two pairs of wings while flies will only have one pair. These pests belong to the wasp category even though they are stingless. Adult sawflies have thick waists, whereas wasps have thin waists.
• Despite being closely related to wasps and bees, the larvae resemble moth and butterfly caterpillars, with the exception that sawflies have 6 or more pairs of legs (prolegs) on their abdomen. Moth and butterfly caterpillars will have 5 or fewer pairs of prolegs. Another differentiating factor is that sawfly larvae will rear up their back legs when touched whereas moth and butterfly caterpillars will not.
• Depending on the species, the coloration of larvae will range between green, black, brown, white, and will either be stripped or spotted. In general, most species of sawfly larvae will have have smooth hairless bodies, whereas caterpillars can appear to be either smooth, hairy, or spiny. Some sawfly larvae are even slimy and translucent, and are referred to as 'slugs'. As the larvae grow their coloration will become lighter and eventually will form a cocoon to emerge as an adult sawfly.

Use the images and description above to help you in properly identifying sawflies. If unsure, then contact us with a photo of your pest by email or visiting one of our store locations. By doing this we can help in proper identification and suggesting the appropriate treatment plan for the pest inhibiting your yard.

Inspection

After properly identifying the sawfly, proceed with an inspection in order to locate the areas infested by this pest and where to focus your insecticide applications.

Where to Inspect

Begin the inspection process by examining the surface and underside of tree and brush leaves as this is the most common place these pests inhibit. Sawflies are plant specific pests that will not move to another type of foliage unless it is a different species. While many species of sawflies feed on tree and shrub leaves they will also feed on some grass types and ornamental flowers.

What to Look For

If you have spotted foliar damage among any trees, shrubs, ornamental plants, or even in turfgrass, then closely examine affected plants for signs of sawfly activity. Look for feeding patterns or the sawflies themselves.

The larvae of many species will consume chunks out of the edges of leaves, similar to how many caterpillars eat. Some species that have slug-like larvae will feed on plant tissue in-between leaf veins. Larvae that hatch from conifer trees will devour older or younger needles, depending on what is available at the time of hatching.

Adult sawflies typically emerge from spring to summer, but they can actually be difficult to spot since they only live for about 1 week as they mate and lay eggs. The presence of dead sawflies can indicate future pest activity for the next season. If you time your inspection before larvae hatch, you can spot eggs in the leaves of their hosts, forming galls, or plump growths.

Treatment

Once you have confirmed sawfly activity, it is time to begin treatment. You will need to wear the appropriate personal protective equipment (PPE) when mixing or applying insecticide products.

Although sawflies look similar to butterfly and moth caterpillars, treatments with BTI will prove to be ineffective. Control of sawflies should be done when larvae is first noticed and less than halfway through their lifecycles as adults are short-lived. Avoid treating too late when the larvae are close to maturing into adults, since by then the damage is already done.

Step 1: Apply Dominion 2L

To treat sawfly larvae, you will need to use a systemic insecticide like Dominion 2L. Dominion 2L is a neonicotinoid that contains imidacloprid and functions as a systemic insecticide to treat sawfly larvae and other species of insects residing in the soil and on the surface of tree, shrubs, flowers, and other types of terrain. It is known for its exceptional residual control where it can stay effective against insects like sawfly for up to 3 months after application.

Determine how much Dominion 2L to use by calculating the square footage of the treatment area. To do this, you will need to measure the length and width of the treatment site in length and multiply together (length X width = square footage). To find acreage, take the square footage and divide it by one acre (square footage / 43,560 sq. ft. = acre).

Dominion 2L can be applied either as a foliar treatment or as a soil drench to treat sawfly larvae. We recommend you use a handheld pump sprayer for low-volume applications or a hose-end sprayer for high volume applications.

To mix for a handheld sprayer, pour half the amount of water with the measured amount of product then add the remaining half of water. Close the sprayer tank lid and shake to ensure even agitation. For hose-end sprayers, you will pour the appropriate amount of product into the container then attach to the end of a garden hose. Remember to not add any water prior to hose attachment as you will spray to add the correct amount of water.

If you are going to apply Dominion 2L as a foliar treatment, output the labeled rate of 1.5 fl. oz. of Dominion 2L per 100 gallons of water.

If you are going to apply Dominion 2L as a soil drench around trees, apply 0.1-0.4 fl. oz. of product per inch of the trunks diameter. Apply the solution uniformly around the base of the tree, especially over the roots, in no less than 10 gallons of water per 1,000 sq. ft.

As a soil drench for shrubs, you will apply 0.1 to 0.2 fl. oz. of product per foot of the shrubs height.

Over flowers, groundcover, and turf, apply 0.46 to 0.6 fl. oz. of product per 1,000 sq. ft. of treatment area. After this application, water the product in.

Once the product has been applied, it will absorb into the plants through the leaves or roots. Labeled pests that attempt to feed off treated plants will be poisoned and will die after approximately 24 hours.

Prevention

After eliminating the sawfly infestation from your property, you will need to ensure that a reinfestation does not return. Listed below are some preventative measures to take against sawflies.

• Lightly dig the ground around tree and shrub baselines during the early spring and again in the fall around suspected host plants. Many sawfly species overwinter by falling to the ground and burrowing as pre-pupa. Some species overwinter as larvae, and some overwinter as eggs. By digging the soil around suspected host plants, you can destroy some pests before they are able to mature into adults.
• From spring through summer, regular watering once a week over and under your plants leaves like lawn, trees, shrubs, and other types of plants with an inch of irrigation during the early morning can wash away eggs or even stop breeding activity altogether.
• Mow your turf when it has reached a height of 3 inches to eliminate any sawfly cocoons or eggs.
• You can also boost your plants health and make it stronger. Healthier plants are more capable of resisting and recovering from pest damage. If an infestation breaks out, prune away afflicted parts to prevent the pests from spreading.
• Finally, keep up with regular pesticide treatments and reapply Dominion 2L every 90 days for year-round control. Ideally, during the summer and early spring months as these periods serve the highest amount of sawfly activity.

Key Takeaways

What are Sawflies?

• Sawflies are stingless wasps that live no more than a week to lay their eggs in the tissue of plant leaves. They achieve their name from the females saw-like ovipositor, which resembles a stinger.

How to Get Rid of Sawflies

• Sawflies should be eliminated during the larvae stage as adults are short-lived and rarely encountered. Apply a foliar or drench treatment with Dominion 2L.

Prevent Sawfly Reinfestation

• Prevent sawfly infestations by regularly maintaining your lawn with a consistent mowing and pruning schedule. Retreat labeled plants and areas with Dominion 2L every 90 days.