Sasha CampbellSo named because of the saw-like ovipositor the female uses to pierce open plants to lay its eggs in, sawflies are in the same order as bees, ants, and wasps [1].
The adult sawfly resembles a wasp, only it doesn’t sting. Moreover, different species of sawflies feed on different plants. Example: European pine sawfly, rose sawfly, elm sawfly, birch sawfly, etc.
These insects go through four stages in life: egg, larva, pupa, and adult. However, the larvae are the main culprits behind most of the damage to plants, so it is vital that you get rid of them quickly.
Sawfly Larvae Identification
Sawfly larvae resemble small worms, and they are often mistaken for caterpillars by gardeners.
However, they must be properly identified because most of the methods used to get rid of caterpillars don’t work on them. Help with identification can be found at Wildlife Insight.
How to Get Rid of Sawflies Naturally
Getting rid of adult sawflies and their larvae can be simple or complex, depending on how many there are.
The following are 13 natural sawfly control methods you can try:
1. Pick Them Off
Simply put on a pair of gloves and pick off the larvae and/or eggs that you find on the leaves or needles.
Next, squish them. You can also drop them in insecticidal soapy water to kill them.
Dropping them in a strong vinegar-water solution may also kill the larvae.
2. Birds
Once mature, the larvae drop to the ground to pupate in the soil. By tilling the soil, you expose the pupa to birds.
Placing a feeder by the affected plants can also attract birds. The birds will then keep coming back once they have something to feed on, where they will also notice any sawfly pupae on the ground.
3. Organic Soap Spray
Since the larvae are soft-bodied, a homemade spray made of 4 tablespoons of organic soap and a gallon of water will help get them off plants.
The stickiness will impede their ability to move, and the film left by the soapy water will kill sawflies by means of suffocation.
4. Use the Water Hose
Spraying the plants with a strong blast of water will knock the caterpillars off the plants. However, be careful not to use too strong a spray, or you might end up damaging the plant.
5. Diatomaceous Earth
To kill pine sawfly larvae and other species of sawflies on plants, you can spray diatomaceous earth or sprinkle it on the plants being attacked.
Diatomaceous also works to keep snails off plants like gooseberries and rose bushes. Moreover, food-grade DE is non-toxic and works better than Sevin (in my opinion).
6. Kaolin Clay
Applying kaolin clay on plants will also keep sawflies and other insect pests away. It will form a barrier that irritates and repels insects.
7. Neem Oil
Neem oil is an all-natural insecticide that comes from the neem tree. It contains azadirachtin, a very potent substance that works against a number of garden pests by killing or repelling them.
To use, combine 4 teaspoons of neem oil with a gallon of water and a little liquid soap. Spray this homemade sawfly killer spray on leaves and other affected areas.
8. AzaGuard
This is a botanical insecticide that works against a number of insect pests, including sawflies. Its active ingredient is also azadirachtin.
Moreover, AzaGuard is safe to use in your organic garden.
9. Vacuuming
This DIY method can also help control sawflies.
If the vacuum has strong enough suction and you’re quick enough, you might be able to catch the adults before they fly off too.
Use a vacuum to suck up the larvae, eggs, and any adult you see. Next, dispose of the critters in soapy water right away.
10. Attract Predators
Sawflies have lots of natural predators. Research will show which species are native to your area and give you tips on how to attract them.
Apart from birds, natural enemies of sawflies include lizards, parasitic wasps, and frogs. Ladybugs also eat sawfly larvae.
Try attracting these natural predators to your garden.
11. Spinosad
Spinosad works great to control pear slugs, caterpillars, and other garden pests.
It attacks the pests’ nervous systems, paralyzes them, and then kills them in about two days.
However, the only drawback to using this sawfly treatment is that it may not work on the eggs. The soft bodies of the pests need to absorb it for it to work, and the eggs have hard shells.
12. Beneficial Nematodes
The nematodes will enter the bodies of larvae and pupae and become parasites that eventually kill them.
Therefore, place beneficial nematodes in the soil around plants. These creatures will go after the sawfly larvae and other bad insects in the soil.
13. Horticultural Oil
This is also a great natural remedy for rose slugs. When applied, horticultural oil covers the sawfly eggs and larvae in a thick film, which eventually suffocates them.
This method is one of the best to use for killing the eggs before they hatch and thus saving the plant from further damage.
What Do Sawflies Eat?
Specifically, the larvae and adults eat the leaves and needles of trees and shrubs. However, some feed exclusively on roses, hibiscus, raspberries, and gooseberries.
You may also find sawflies on barberries, plums, bottlebrushes, creeping Jenny, dogwoods, willow trees, mallow, and azaleas. They feed in groups.
Damage to Crops
The damage the larvae can do to the plants they feed on can range from slight to severe. It depends on how many of them there are and the condition of the plants they’re eating.
Sawfly damage to leaves or needles comes in the following forms: holes in leaves, leaves eaten down to the veins, galls on the leaf surface, or rolled-up leaves.
Healthy, mature plants are less susceptible to this kind of damage. However, young or weak plants will show greater damage.
Takeaway
Whether you call them sawfly worms, rose slugs, or pear slugs, sawfly larvae can be a problem in your garden. While they won’t harm people or animals, they can cause major damage to some plants.
For a healthy garden and/or orchard, getting rid of an infestation is the best course of action.
Using these natural pest control methods will be more beneficial to your plants than any toxic insecticide ever will be.
Thank you so much! This is the most comprehensive article I have seen for dealing with these ornery pests! They devastate my pear tree every year and as an organic gardener I have been struggling to get rid of them. Thanks for the abundance of new “tools”.