Crape myrtle bark scale is relatively easy to identify. They could also be mealy bugs, a scale-like insect pest with visible legs that doesn't move around much. The sac is about 3 mm long and 1.5 mm thick. Treatment with horticultural oil … Crawlers attach to the bark and feed in crevices and branch forks. Photo credit: Oregon State University. Summer oil and other insecticides can be used in mid-June or early July for the crawlers. June 2, 2015. To contact an expert in your area, visit https://extension.msu.edu/experts, or call 888-MSUE4MI (888-678-3464). (Possibly two in southern states), Leaf yellowing is often visible after June or July, Sooty mold growing on honeydew can be found under tree or on limbs, White waxy threads of the females egg sac near twig crotches prior to June or July, Small winged adults males are generally on leaves around August through September, Crawlers are reddish, tiny, mobile, and typically found around June or July. Beneficial predators and parasites will usually provide adequate control of light bark scale infestations. This will suffocate adults and many small “crawlers”. Mature female scale are about 0.13 inch long and appear like white cottony sacs, often located on twigs and stems of azalea, especially in branch axils. It has been reported in the Eastern US, as well as Belgium and Russia. Eggs are deposited into the white waxy egg sac in late April, Crawlers prefer branch crotches and twigs where they insert their mouthparts, There is one generation per year. Sooty mold growing on honeydew can be found under tree or on limbs. At dormant or delayed-dormant, use with a horticultural oil. Scale produces a waxy coating that makes them difficult to kill. pyriproxyfen (Esteem) at 0.1 lb ai/a. Scale sounds and looks a lot like a plant disease, but the term actually refers to infestation by any one of more than 7,000 species of tiny sap-sucking insects.Scale insects typically adhere to the stems, branches, and sometimes the leaves of plants to feed on sap, and they have a shell-like bump appearance, which sometimes causes them to be mistaken for a fungal or bacterial disease. Dave Smitley, Michigan State University Extension, Department of Entomology - Bayer Advanced Tree and Shrub Insect Control (imidacloprid) provides season-long, systemic control of azalea bark scale. Azalea bark scale (Acanthococcus azaleae) infestations can be severe. Adult females are felt-like white or gray encrustations that stick to crape myrtle parts ranging from small twigs to large trunks. Check out the Agribusiness Management B.S. Azalea bark scale, Eriococcus azaleas Comstock, Eriococcidae, HEMIPTERA. Symptoms of their sucking include honeydew, sooty mold, and considerable leaf yellowing and die back. Research is underway at this time to determine if enough imidacloprid will be present in the following year (one year after a basal drench is made) to be detrimental to bees when the azaleas are blooming. When crushed, these scales exude pink “blood”-like liquid. This can be a difficult pest to control and it may take m… 2). Azalea Bark Scale Diagnostic Guide; Azalea Lace Bug Diagnostic Guide; Azalea Whitefly Diagnostic Guide; Bagworms Diagnostic Guide; ... Each one contains signs and symptoms, treatment strategies, and treatment expectations designed to help you properly diagnose diseases and provide effective solutions. 1) Azalea bark scale, Eriococcus azalea. White waxy threads of the females egg sac near twig crotches prior to June or July. If the canopy of your azalea is thinning or yellowing in places or has some dead branches, look for a crusty covering of scale insects on the stems, or white, waxy egg masses produced by the females (see photos). This sap-sucking scale can cause serious harm to your favorite Azalea or Rhododendron. --Sarah in Drexel Hill, PAA. If scales are juicy, they are alive. Next, in late March, apply a systemic insecticide called Bioadvanced Tree & Shrub Insect Control to all your crepe myrtles according to label directions. Use all neem oil products by following the instructions since, as an oil, there is greater risk of … Q&A related to Azalea Bark Scale. We recommend using Organocide 3-in-1 Garden Spray to control azalea bark scale. As with most insects, there are several life stages and the appearance of CMBS changes with the stages. Beneficial insects, such as wasps, control scale population. To break their life cycle, spray once a week for 4 consecutive weeks. Heavy infestations can be sprayed again two weeks later. This product is mixed in a bucket of water and poured around the base of the shrub. Honeydew can be an inconvenience as well. MSU is an affirmative-action, equal-opportunity employer. Because imidacloprid is a systemic insecticide that is absorbed through the roots and moves up into the foliage, some insecticide may move into the flowers. Scale treatment options If azalea bark scale is found, Michigan State University Extension recommends spraying infested plants with a 2 percent concentration of a horticultural oil in mid-July. The insect is hidden from view by the egg sac (ovisac), a covering of felted/matted waxy threads (Fig. Examine the bark of host plants to determine when or if the crawlers are active to help in the timing of any needed treatments. Dr. Smitley’s work is funded in part by MSU’s AgBioResearch. Photo credit: Clemson University, USDA Cooperative Extension Slide Series, Bugwood.org. Black Vine Weevil, Otiorhynchus sulcatus Recognition and Life Cycle A more complete list of azalea problems is at azalea diagnosis. Eggs, crawlers and adults under the wax are red. Sorry, your blog cannot share posts by email. The adult females (1/8 inch) with their white egg sacs are most noticeable in May and June. This article was published by Michigan State University Extension. Consider hand–removal by squishing the scales to prevent populations from increasing. For more information, visit https://extension.msu.edu. One product with good directions on the label for applying imidacloprid as a drench is Bayer Tree and Shrub Insect Control. Leafminer. To have a digest of information delivered straight to your email inbox, visit https://extension.msu.edu/newsletters. A late-winter or early-spring soil drench of imidacloprid systemic insecticide around your azaleas can control azalea bark scales for an entire growing season. We will continuously be adding to this list. The adult female azalea bark scale can be described as dark red with short legs and antennae and long, sucking mouthparts. However, another threat to azaleas, as well as rhododendron and Pieris or andromedas, is azalea bark scale (Eriococcus azaleae). Apply either at dormant or delayed-dormant for the overwintering stage, or as an in-season cover spray for control of the crawlers. Thanks! Female insects are approximately 0.125 inches long. Immature scales, 0.0625-0.125 (1/16-1/8) inches long, overwinter on the stem, maturing quickly the next spring in late May. Do not apply oil sprays when the temperature is above 90 °F or to drought-stressed plants. Protect bees and other pollinators by waiting until after the shrubs are done blooming before applying the basal soil drench. An oil spray applied after the crawlers emerge is usually very effective in controlling azalea bark scale, but keep checking each year and spray again when necessary. ; Will Zylam Liquid Systemic Insecticide work on the Crape Myrtle Bark Scale? Bark scale originates from China and was brought to the U.S. in 2010. Azalea bark scales. Later in summer or next spring you can determine if any live scales are present by using a fingernail to scrape off some of the crusty buildup on the stems. Neem oil products work by suffocating the insect. Close-up of Azalea bark scale egg masses on infested branches blackened by sooty mold. A&M has identified this pest as Eriococcus lagerstroemiae, and suspects that it was brought into the U.S. on a crape myrtle plant. Winter-hardy azaleas are promoted as suitable for cold hardiness zones 6 or higher. DESCRIPTION. I think they are Azalea Bark Scale. If scales appear again in two weeks repeat spraying for another week. Several other products are also available that contain imidacloprid. Scale insects appear as small raised bumps on the twig or leaf. A: You have a big infestation of cottony cushion scale. Warning : Horticultural chemicals tend to work because they are harmful. Notify me of follow-up comments by email. The insect is hidden from view by the egg sac, a covering of felted or matted waxy threads ().The sac is about 3 mm long and 1.5 mm thick. program! Branch dieback. Insecticidal soap, made from potassium salt of fatty acids, works by penetrating and destroying the outer shell or membrane of the insect causing it to dehydrate and die. Show your Spartan pride and give the gift of delicious MSU Dairy Store cheese this holiday season! Contact your local county extension office for treatment methods. Are pesky Azalea bark scales attacking your blueberry plants? The 4-H Name and Emblem have special protections from Congress, protected by code 18 USC 707. Females produce white, waxy egg masses in late June to early July. It also leaves a micro-film on the plant that will repel egg laying females because they know it’s harmful to their eggs. There is one generation per year in Michigan. Hosts include andromeda, azalea, rhododendron, hawthorn, poplar, willow, and most recently, blueberry in the Pacific Northwest. Scale. Rhododendron Borer. Bark Scale along the branch of a Crape Myrtle. The scale insects have long, needle-like mouthparts they insert into the plant for sucking plant juices. If they're not moving around, small, fuzzy, white caterpillars might be one of the thousands of species of scale. If azalea bark scale is found, Michigan State University Extension recommends spraying infested plants with a 2 percent concentration of a horticultural oil in mid-July. The azalea bark scale, Eriococcus azaleas, is a prominent pest of rhododendron, azalea, and huckleberry (Vaccinium spp.). Make cover spray applications when scale crawlers first emerge. Spray late in … Bark scales Azalea bark scales cause yellowing and a soot or mold appearance on stems. ; What is the ratio of Hi-Yield 55% Malathion Insecticide Spray to kill mulberry caterpillars? Good culture practices are a key element of keeping plants resistant to bugs and germs. PHI 7 days. Michigan State University Extension programs and materials are open to all without regard to race, color, national origin, gender, gender identity, religion, age, height, weight, disability, political beliefs, sexual orientation, marital status, family status or veteran status. Azaleas can tolerate low populations of this bark scale without significant damage. Can I use Pivot 10 for azalea bark scale?Cottony maple/taxus scale? Identifying azalea bark scale early gives an advantage in treatment. If there are no yellowing leaves, no treatment is necessary. Follow their label safety precautions such as gloves and other protective measures to avoid personal harm, and follow their label rates of dilution and application to avoid harm to the plants and environment. I purchased some horticulture oil this morning from Lowes but I'm skeptical about it's effectiveness of getting rid of mature bark scale. Scraping the scales off of the rhododendron effectively eliminates them. MSU is an affirmative-action, equal-opportunity employer, committed to achieving excellence through a diverse workforce and inclusive culture that encourages all people to reach their full potential. It is one of the only scales known to infest crape myrtles. Spray after the azaleas are done blooming to avoid spraying over bees and other pollinators, and to avoid flower injury. Azalea bark scale – (737) Oak lecanium scale – (789) Beech scale – (800) Japanese maple scale – (829) Calico scale – (834) Cottony maple scale – (850) European fruit lecanium scale – (940 DD) Summertime scale treatment options. To treat, eliminate the insects and prune any dead or dying parts of the plant. If your azalea shrub has thinning or dead branches, look for a crusty covering of scale insects on the stems. The red eggs are laid within the egg sac, occupying the void left by Dilute the concentrate version at 3 fl oz per gallon of water and directly spray onto the bark to control the nymphs before they become adults. Reference to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned. Scale insects feed on bark or leaves, producing red or yellow spotting on the leaf or bark of twigs. https://www.giroudtree.com Azalea Bark Scale can destroy beautiful Azalea shrubs. This means that southeast and southwest Michigan are borderline climates for growing azaleas, and planting anywhere else in Michigan will require excellent winter protection. This information is for educational purposes only. So in Michigan, when we grow azaleas we are usually focused on finding protected sites and providing winter protection by covering the ground over the roots with mulch and draping protective burlap over the entire plant. CMBS might be able to overwinter in the adult female and egg life stages, and crawlers and later stage nymphs have been observed overwintering under the loose bark and in cracks and crevices of crapemyrtles in our area. Affected shrubs may be covered with sooty mold or appear as white, cottony masses within the forks of branches. 4 through 6). Leaf yellowing is often visible after June or July. Bark Scale Treatment on Azaleas. Infested stems and leaves under infested stems may also turn black from the black, sooty mold fungus that grows on the sugary liquid waste excreted by the scale insects. Two weeks later spray acetamiprid (Ortho Fruit … RTS = Ready to Spray (hose-end applicator) RTU = Ready to Use (pre-mixed spray bottle) Drench = Add to water and pour around base of plant. Issued in furtherance of MSU Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Up close, CMBS is white t… Many diseases and other problems can be prevented by following the recommended cultural practices for proper planting and care. If the crusty residue is dry and flaky, the scales are dead. Many people who call us describe their trees as covered in white dots, or white cotton like bumps. Photo credit: A.L. Dead scales may remain on stems for a year or more. In one year, there could be at least two generations of CMBS. An alternative treatment for azalea bark scale is a basal soil drench with imidacloprid. Rhododendrons and azaleas are some of the most popular spring-flowering shrubs in the landscape, and healthy plants can give years of pleasure. More information on successfully growing azaleas and rhododendrons is available in the fact sheets HGIC 1059, Azalea Care; HGIC 1058, Azalea Planting; and … This will smother both adult and immature scales. Azalea Bark Scale – This azalea plant pest occurs most often in the eastern United States. A scale infestation is indicated by sooty mold on leaves, yellowing of leaves, and twig dieback. Azalea bark scale. Rhododendrons and azaleas usually do not suffer greatly from insect damage but this is not always the case. Spray after the azaleas are done blooming to avoid spraying over bees and other pollinators, and to … Adult – The adult female azalea bark scale is dark red with short legs and antennae and long, sucking mouth- parts. This is a pest that generally does not kill hosts, rather it causes aesthetic damage. Larvae hatching from the eggs are called "crawlers" because they are the most mobile life stage of the scale insect. First, after its leaves drop, apply dormant oil to the trunks and branches. Coating azalea leaves with insecticidal soap is also an effective treatment, as is spraying the plants with horticultural oil. ; Would Captain Jacks Deadbug Brew Concentrate be effective for treating Azalea Bark Scale? Post by ECUPirate » April 8th, 2015, 9:24 am Does anyone have any recommendations on how to get rid of bark scale on azaleas? These branches should be removed and destroyed. Azalea Bark Scale, Eriococcus azaleas, was discovered in 1881 and is a major yearly pest for Azaleas, Rhododendrons, and Huckleberries.Although the pest usually does not kill the host tree, it causes aesthetic damage, weakens the tree, and can cause honeydew and sooty mold to develop. Antonelli, Close-up of azalea bark scale egg masses. Soft Scales Found on Trees and Shrubs - The following are examples of commonly found scale insects that infest deciduous, broadleaf, and evergreen plants. It is applied as a soil drench around the base of affected plants … Jeffrey W. Dwyer, Director, MSU Extension, East Lansing, MI 48824. Treatment is in two parts: spray under all leaves and around all stems thoroughly with horticultural oil. On new growth and in heavy infestations, the scales may be distributed more uniformly on the branch (Figs. Post was not sent - check your email addresses! The azalea bark scale, Eriococcus azaleae Comstock, can be found on a variety of hosts grown in nurseries and landscapes including azalea, rhododendron, andromeda, hawthorn, poplar, willow, and most recently, it has been found infesting blueberries in the Pacific northwest. The crawler stage of azalea bark scale soon after egg hatch. 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