Start looking for sawfly larvae on the lower surfaces of your rose leaves in mid-spring. The key to effective rose sawfly control is to find the larvae while they are still small and before the damage becomes severe. Handpicking is good if you have a small garden or if their population is small. Older roseslugs chew holes through the material close to the midrib or skeletonize leaves entirely if populations are high. Kristi Waterworth started her writing career in 1995 as a journalist for a local newspaper. Those that belong to the Argidae family are common in birch, oak, elm, and rose … In addition, the mature larvae of the bristly roseslug (Cladius difformis) bear many stiff bristles along the length of their bodies. If you inspect the leaves closely you will see the culprit! Their larval forms, reaching up to 3/4 inch, superficially resemble semi-transparent caterpillars or dark, shiny slugs. The contact insecticide carbaryl (click for sources)) offers good control if sprayed on the whole rose. The control and elimination of sawflies are possible through natural solutions that do not pose harm beyond its target. The Roseslug Sawfly, Endelomyia aethiops During the months of May and June in the Northeast you may have noticed leaf discoloration in the form of blotches on your rose leaves (Figure 1). Roseslugs feed on rose foliage, but damage varies depending on the age of the larvae involved. Sawflies are stingless wasps that measure less than 1/2 inch long and pose no risk to gardeners. Different species of sawflies feed on different plants. Younger larvae may leave a thin layer of white, papery tissue behind. The early feeding damage causes “windowpanes” of transparent leaf tissue on the leaf as the larvae feed on the surface of the leaf. The adults have yellow abdomens with mainly black thorax and heads. Large rose sawflies have pale spotted black, green and yellow larvae that eat the leaves of roses, sometimes causing severe defoliation. Below are some of the solutions that work best: One of the most common ways to get rid of them is through mechanical control. Small numbers of roseslugs are easily handpicked or blown off roses with a garden hose. From there, her meandering career path led to a 9 1/2 year stint in the real estate industry. These beautiful bushes are bothered by many insect pests, including the sawfly, whose larvae can be very destructive to rose leaves. © Copyright 2020 Hearst Communications, Inc. Waterworth received a Bachelor of Arts in American history from Columbia College. Rose sawfly (sometimes called rose slug) larvae are a common pest of roses. If you look closely you can see some larvae still present on some of the leaves. For large-scale infestations, this will not work as it will be exhausting. Roses (Rosa spp.) You can choose from various control methods to kill rose slugs and keep your rose plants looking fabulous and smelling great. These young pests, collectively known as roseslugs, feed at night, damaging roses until they pupate. It is a small, narrow bodied larva called the roseslug sawfly… Roses can also be attacked by other sawflies such as the rose leaf-rolling sawfly and rose slug sawfly or slugworm. Although spinosad is very effective, a few pest insects have developed resistance to this chemical. Control heavy sawfly feeding by spraying your roses with membrane-disrupting insecticidal soap. Spinosad can be an effective treatment for roseslugs any time of the year if you completely cover leaf surfaces. The adults have yellow abdomens with mainly black thorax and heads. Regularly check for rose slugs and prune off the leaves with noticeable eggs or signs of rose slug damage. A strong spray with a garden hose can also get rid of them. Imidacloprid (click for sources)) is a systemic which can be applied to the soil around the roses in spring before feeding activity is noticed. bring heavenly fragrance and delicate flowers to home gardens in U.S. Department of Agriculture plant hardiness zones 2 through 11, depending on species. Help spinosad remain effective by using it as a treatment of last resort and instead trying nonchemical control methods first. Check plants at night for roseslugs before applying this product since other pests may cause damage similar in appearance. Sawfly Identification. When to Spray Roses With Spinosad for Sawfly. Spending just a few minutes a day on each rose bush checking and squishing is an effective and organic method of control. It's important to get control over sawflies early in the season since they can produce many generations in a year, depending on the species involved. sawfly damage. Roses (Rosa spp.) There is no need to treat the rose … About Rose Slugs Despite their name, rose slugs aren't actually slugs. As the larvae grows larger, the feeding damage begins … Conifer sawflies, for instance, are found in coniferous trees, such as pine and spruce. Also, water in the early daytime so your roses … You can also … These young sawflies may feed from the top or the bottom of the leaf. Identifying Sawfly’s Damage Plants Affected. Treatments such as spinosad are effective against these bugs when applied properly. Large rose sawflies have pale spotted black, green and yellow larvae that eat the leaves of roses, sometimes causing severe defoliation. European rose slug (sawfly) University of California Statewide Integrated Pest Management Program: Roses: Insect and Mite Pests and Beneficials, University of California Statewide Integrated Pest Management Program: Sawflies, Clemson Cooperative Extension: Rose Insects and Related Pests, University of Nebraska-Lincoln Extension: Roseslugs Fact Sheet, University of Kentucky Extension: Roseslugs Have No Shame, Cornell University: Resource Guide for Organic Insect and Disease Management, University of California Statewide Integrated Pest Management Program: Spinosad. Apply spinosad only in the evening to protect bees from this chemical. Instead, they are the larvae of rose sawflies, non-stinging, flying insects that belong to the wasp family (Tenthredinidae). Apply food-grade Diatomaceous Earthfor long-lasting protection. Spinosad can be applied at any time roseslugs are active but does not persist for more than 16 days under ideal conditions, requiring weekly applications when combating a pest with the potential for multiple generations like the sawfly. Since 2010, she's written on a wide range of personal finance topics. Sawfly larvae love the tender new leaves of a rose. Insecticidal soaps are also effective, but test a small spot on the affected rose a few days prior to treatment to check for sensitivity. Roses can also be attacked by other sawflies such as the rose leaf-rolling sawfly and rose slug sawfly … You can also pick them off and use soapy water to kill them.