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 sawflies in your yard, both their adult and larvae stages.

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

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

Though a heavy amount of damage surrounds the sawfly species, their larvae 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 must be certain that the insect invading your property is a sawfly species. Misidentification can lead to using the wrong insecticides, which can be a waste of your finances and time. While sawfly species vary in some of their features, they share a few distinguishing characteristics.

• There are thousands of 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 damage to different species of trees and shrubs, then there 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, sawflies look like flies or wasps, but upon closer examination, they reveal that sawflies have two pairs of wings while flies have only 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, except 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, and white, and will either be stripped or spotted. In general, most species of sawfly larvae will have smooth, hairless bodies, whereas caterpillars can appear to be either smooth, hairy, or spiny. Some sawfly larvae are slimy and translucent, called 'slugs.' As the larvae grow, their coloration will become lighter and eventually form a cocoon to emerge as an adult sawfly.

Use the images and description above to help you properly identify sawflies. If unsure, email us with a photo of your pest or visit one of our store locations. We can then help you properly identify the pest inhibiting your yard and suggest the appropriate treatment plan.

Inspection

After properly identifying the sawfly, proceed with an inspection 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 inhabit. 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 turfgrass, 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 with slug-like larvae will feed on plant tissue between leaf veins. Larvae that hatch from conifer trees will devour older or younger needles, depending on what is available during hatching.

Adult sawflies typically emerge from spring to summer, but they can be difficult to spot since they only live for about 1 week as they mate and lay eggs. 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 ineffective. Sawfly control should be done when larvae are 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 must 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 trees, shrubs, flowers, and other types of terrain. It is known for its exceptional residual control, where it can stay effective against insects like sawflies 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 them together (length X width = square footage). To find acreage, divide the square footage by one acre (square footage / 43,560 sq. ft. = acre).

Dominion 2L can be applied as a foliar or soil drench to treat sawfly larvae. For low-volume applications, we recommend using a handheld pump sprayer or a hose-end sprayer.

To mix for a handheld sprayer, pour half the water with the measured amount of product and add the remaining half. 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 and attach it to the end of a garden hose. Remember not to 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 to 0.4 fl. oz. of product per inch of the trunk diameter. Apply the solution uniformly around the tree's base, 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 shrub's height.

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

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

Prevention

After eliminating the sawfly infestation from your property, you must ensure that 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 around suspected host plants in the fall. 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 mature into adults.
• From spring through summer, regular watering once a week over and under your plants' leaves, such as lawns, 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 plant's 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, these periods serve the highest amount of sawfly activity during the summer and early spring.

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 female's saw-like ovipositor, which resembles a stinger.

How to Get Rid of Sawflies

• Sawflies should be eliminated during larvae 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.