Soft Scales (see photo gallery) Soft scales, family Coccidae, grow up to 1⁄4 inch long and have a smooth, cottony, or waxy surface. Oystershell scale insect is killing my Hedge dammit! Postmedia is committed to maintaining a lively but civil forum for discussion and encourage all readers to share their views on our articles. Over time, the scale ‘shells’ will reproduce and spread over large areas of the tree’s woody branches. However, most notably to me, is the problem of Oystershell scale. There are two main groups of tree scale—soft and armored (hard). Especially cotoneaster, a hardy bush which can endure harsh prairie winters but is very susceptible to this ravenous aphid-like bug. The best defence is to keep up on yard maintenance and inspect your plants for any signs of pests on a regular basis. Controlling Euonymus Scale Bugs. Close. The next issue of Calgary Herald Headline News will soon be in your inbox. Generally we need some sustained  warm weather while the plant is dormant to be effective with dormant oil. Keeping your garden, including all plants, shrubs and trees healthy, watered and happy is your best first defence. Oystershell scale Lepidosaphes ulmi (L.) Magnolia scale, Neolecanium cornuparvum (Thro. ) Check the label to make sure that  the product can be used properly. Oystershell scale can be found on many different shrubs and trees, the most common hosts for our area being lilac, cotoneaster, and dogwood, and injure plants by … The cotoneaster is a shrub commonly used in Calgary, as they can easily be grown into decorative hedges. Insecticidal soap can also be sprayed on houseplants to kill scales. Other trees and shrubs can be affected by this scale or similar scales, so diligence and removal are important.  Fortunately the really bad situations seem to be restricted mostly to cotoneasters, at least with oystershell scale. They are found mainly on stems, and only occasionally on leaves. Elm scale - tiny crawling insects on leaves, twigs and branches. They are extremely hardy – perfect for Calgary’s harsh climate – and are identifiable by their pink flowers in the spring, glossy, oval-shaped leaves and red berries in the fall. * Fletcher scale * Apple aphid on crabapples * Honeylocust spider mite. Compare these stems to healthy stems. However, over-fertilization favors scale buildup. Cotoneasters with healthy root systems will quickly re-grow. Symptoms of infestation don’t usually show up until your shrub or tree is heavily infested, making this a difficult pest to fight. It’s important to act early in the infestation progression as once you can easily notice it, the infestation is usually quite severe. Armored scales, such as the oystershell scale (Lepidosaphes ulmi), can infest viburnum and cause branch dieback.If the infestation is severe enough, they may kill the shrub. If you don't see it please check your junk folder. 0. We offer flexible appointments, with our online services allowing advanced booking and on the day appointments alongside a range of alternative appointments to suit your busy lifestyle. Look for areas of crusty, rough looking bark. If you scrape your fingernail over them they can be dislodged. The male scale covers are elongate and white with three longitudinal ridges. Inspecting plants that are prone to Oystershell is a good preventative measure. Once hatched, the “Crawlers” feed on fluids found in the twigs and branches; they then permanently attach to the branch, developing a hardened shell that protects them from predators, the elements and most pest-control methods. Oystershell Scale - small clusters of oyster-shaped “shells” that cover bark on shrubs and trees Satin moth - feeds on poplar tree leaves. How do you know if your shrub or hedge is cotoneaster?  If it has a nice fiery red colour in fall like the image above and persistent black berries it’s probably cotoneaster. This can be an elusive combination of events in our climate. © 2021 Calgary Herald, a division of Postmedia Network Inc. All rights reserved. The bad news is that it’s hard to kill oystershell scale.  Dormant oils could theoretically work but  it’s too late now that the shrubs have leafed out.  Other sprays do not penetrate the protective ‘shell’ of this sucking scourge.Â. The insecticide that oils are used for the most are armored scales (pine needle scale, euonymus scale, oystershell scale). ... on Taxus cuspidata was undertaken on two 10-foot-long taxus hedges averaging about 4 feet in height. Following a recommended fertility program and watering regime will promote plant health. For these plants use a pyrethrum spray. Archived. Scale insects feed on shrubs' sap using their long, piercing mouthparts, causing twig and branch dieback and sometimes killing the plants. This is a sucking insect that can cause dieback. Scales tend to thrive on stressed plants. Find out more... Telephone consultations. Fire Blight - a bacterial disease that browns and kills leaves, flowers and branches. A healthy plant can fight off many pests and rebound from infestations more easily. Oystershell scale spreading through Calgary hedges The oystershell scale insect is spreading through cotoneaster — a plant widely used in Calgary for hedges, shrubs and bushes. Inspecting plants that are prone to Oystershell is a good preventative measure. The best time to get rid of waxy scale in your garden is when the scale are juvenile and travelling between plants. This pest only reproduces once per year, with the egg hatch occurring in early to mid June over an approximate ten day period. Sign up to receive daily headline news from the Calgary Herald, a division of Postmedia Network Inc. A welcome email is on its way. This handy hedging shrub has few enemies but its arch nemesis is the pest called the oystershell scale. The oystershell scale insect is spreading through cotoneaster — a plant widely used in Calgary for hedges, shrubs and bushes. No bark is showing – all that bumpy stuff is oystershell scale. Oystershell Scale. Oystershell Scale (Lepidosaphes ulmi) Heavy infestations of this armored scale will cause yellowing and wilting of leaves and eventual dieback of branches. Mix about 5 tablespoons of insecticidal soap or a very mild dish soap into 1 gallon (3.8 L) of water. Unauthorized distribution, transmission or republication strictly prohibited. Shaped like rounded bumps 4. Systoxo emulsion was sprayed onto the hedges on April 30 at the rate of and 1 pint in 100 gallons Of It’s an organic spray but, if possible, spray in the evening to avoid harming any beneficial insects in your garden. Elm Scale - tiny crawling insects on leaves, twigs and branches. There was an error, please provide a valid email address. Elm scale, which is a soft scale insect, and Oystershell, which is a hard shelled variety can be treated quickly and effectively with natural treatments that promote regeneration of the tree, without harming surrounding shrubs and lawns. Scale … This advertisement has not loaded yet, but your article continues below. Severely prune back heavily infested branches and protect new growth with insecticide applications. Scale insects also secrete a sticky liquid called honeydew, which promotes the fungal disease black sooty mold. This scale insect has been destroying many of the beloved hedges in this city. The damage they cause only gets noticed when the condition is too late. The oystershell scale can overwinter as full grown females that are attached to the bark, or as eggs that are beneath the adult scale … At maturity, soft scales are usually larger and more rounded and convex (humped) than armored scales. Visit our Community Guidelines for more information and details on how to adjust your email settings. This stage only lasts for a week to ten days, so it’s important to act quickly: Apply a Horticultural Oil (this helps suffocate the “shells”). It has the appearance of small clusters of oyster-shaped “shells” that cover bark on shrubs and trees. Oystershell eggs typically hatch in late May or early June and the active ‘crawlers’ that emerge move about to find new sites to feed. We apologize, but this video has failed to load. Damaging species include cycad scale, euonymus scale, oystershell scale, and San Jose scale. Infested plants have an unhealthy appearance overall. Identifying Oystershell Scale. Cherry laurels are also prone to scale insects such as the white prunicola scale. Untreated, this insect causes severe die back of the host plant as it sucks away plant fluid. Pour the soap into a spray bottle and spray the plant, including the undersides of the leaves and stems, until the soap solution begins to drip. Symptoms of infestation don’t usually show up until your shrub or tree is heavily infested, making this a difficult pest to fight. This website uses cookies to personalize your content (including ads), and allows us to analyze our traffic. I have cut my cotoneasters to the ground twice to rejuvenate them (for other reasons than scale) and they are back happy and healthy.  The best time to cut a shrub to the ground to rejuvenate them is winter when the plants are dormant and maximum energy is stored in the roots. When it is severe, the only treatment is completely pulling down the hedges, spraying the regrowing spouts, … ... "Oystershell scales begin life as over wintering eggs under the shells of their now dead mothers. Oystershell scale is considered a serious pest on Cotoneaster shrub- which is a popular choice for hedges in our city. 365 Bloor Street East, Toronto, Ontario, M4W 3L4. To monitor for this pest look for tiny (3mm), oyster shell-shaped, brown to gray scale covers on the bark of wilting or dead branches. Posted by 4 years ago. We ask you to keep your comments relevant and respectful. If practical, improve plant sites to reduce stress and promote growth. Oystershell Scale Attacking Cotoneasters and Apple Trees. Both use long, needle-like mouthparts to suck out sap from the host tree or plant.Characteristics of Soft Scales 1. Join the mailing list to receive daily email updates. Oystershell scales suck the fluids of cells underlying the bark, often killing the cells at the feeding site. Oystershell scale is considered a serious pest on Cotoneaster shrub- which is a popular choice for hedges in our city. Please try again. Natural pest control: ladybugs (lady beetles), lacewings and other natural predators are helpful in controlling outbreaks. Other options tap here to see other videos from our team. Look for branches with oyster-shell shaped bumps, leaves that are turning yellow, and branch dieback or gaps in your hedges. Fruit trees, lilac, ash, maple, dogwood, poplar, and willow. After hatching in spring, the small white crawlers emerge and move a short distance. The most practical ‘cure’ is to cut all dead patches to the ground.  In many cases this means cutting the whole hedge to the ground.  It sounds drastic, but cotoneasters respond quite well to drastic pruning.  A new hedge will grow back within a few years as long as the roots are healthy.  Although I’ve never tried it, it may be a good idea to apply dormant oil to the regrowth sometime in spring before the shrubs leaf out. Oystershell scale is considered a serious pest on Cotoneaster shrub- which is a popular choice for hedges in our city. Once dead patches are easily spotted, pruning out affected stems or cutting the entire hedge to ground level is the most effective control. To find out if your cotoneaster hedge has oystershell scale, check the stems in dead patches. Usually larger than armored scales 3. Oystershell Scale - small clusters of oyster-shaped “shells” that cover bark on shrubs and trees Dutch Elm Disease - … Oystershell scale continues to be an insect which plagues plants like cotoneaster shrubs in the Calgary area. Oystershell scale: a major problem in cotoneaster hedge in Calgary In last few years, the cotoneaster hedges are severely infested by Oystershell scale which causes die back of the hedge, fail to leaf out and make dead patchy spots.Oystershell scale affects several … Monitor for these scale insects - look along the branches and stems for small disc or oystershell shapes that can be scraped off. Closely inspect the branches. The female scale covers are broadly oystershell-shaped and dark brown. Symptoms. It’s called oystershell scale and its claim to fame is killing off hedges and bushes. The oystershell scale is a sneaky and dangerous insect pest that gouges on shade, hedge and shrub crops. Don’t use oil-based sprays on ferns or fine-leafed palms. Don’t have a shell, instead they secrete a cotton-like or waxy substance over their bodies for protection 5. Some types of soft scales include lec… By continuing to use our site, you agree to our Terms of Service and Privacy Policy. A population of scale on euonymus shrubs can go through to 2 to 3 generations in a single summer. In last few years, the cotoneaster hedges in Calgary are severely infested by Oystershell scale which causes die back of the hedge and makes dead patchy spots. Symptoms Symptoms of infestation don’t usually show up until your shrub or tree is heavily infested, making this a difficult pest to fight. If the weather was very cold and there was more snow, … If you notice your Cotoneaster hedge is looking sparse, or there are bare, dry brown areas with crisp dried brown leaves, your hedge may be suffering from an Oystershell Scale infestation. Oystershell scale. Friday, May 21, 2010 - What's Wrong With Your Hedge? We encountered an issue signing you up. When Oystershell scale eggs hatch in early June and become “crawlers”, they are most vulnerable to treatment methods. Oystershell scale is one of a number of scale insects we might get on various plants.  These mostly immobile creatures affix themselves to, and suck the juices out of their hapless victims.Â. Euonymus scale treatment is a game of timing. Oystershell scale. Oystershell scale is an introduced pest in Calgary. Cotoneasters are so forgiving of drastic pruning that you could probably get away with giving them a ‘buzz cut’ any time of year if you really want to.  At the very least cut the dead stuff and any stems that you can see scale on right away and dispose of them. If you would prefer not to come into the surgery for an appointment you can book to have a Telephone consultations with a doctor or nurse. They are about 1-2 mm (1/16 inch) long. Fire blight - a bacterial disease that browns and kills leaves, flowers and branches. Now is a good time to check plants for evidence of Oystershell scale insects overwintering from last season. The pest, which is an armored scale, is one of the most common of … Produce a sugary liquid called honeydew 2. Appointments. Read more about cookies here. We have enabled email notifications—you will now receive an email if you receive a reply to your comment, there is an update to a comment thread you follow or if a user you follow comments. Try using insecticidal soap. Comments may take up to an hour for moderation before appearing on the site. They occur in greatest numbers on the lower branches and leaves of the plant. The best time for euonymus scale treatment is when they’re in their crawler stage, before they grow their protective shells. Hopefully nothing’s wrong with your hedge, but I have been getting quite a few questions this spring about cotoneaster hedges with big dead patches.  Cotoneasters (pronounced ‘co_TONY-aster’ believe it or not) is about the best hedging shrub we have and normally it’s a reliable and tough little plant.  This handy hedging shrub has few enemies but its arch nemesis is the pest called the oystershell scale.  To find out if your cotoneaster hedge has oystershell scale, check the stems in dead patches.  Oystershell scale looks like tiny brown oysters and they completely cover the stems they kill. A scale insect problem can be seen on trees in the form of small brown bumps, which look like small oyster shells attached to the branches and trunk of the tree. Will cause yellowing and wilting of leaves and eventual dieback of branches oyster-shell shaped bumps, leaves that turning. And happy is your best first defence from our team not loaded yet but! 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