Pest description and damage Hemlock scale feed on the needles of Eastern hemlock (Tsuga canadensis) and spruces (especially Colorado blue). 566 pp. Do not contaminate forage, streams, or ponds. Perhaps the biggest pest of Hemlock trees is the Hemlock woolly adelgid. Entering your postal code will help us provide news or event updates for your area. Hemlock Trees and their Pests. Consider having a licensed arborist do the sprayi… Females have three developmental life stages after the egg, and males have five. Treatments for hemlock woolly adelgid If you have confirmed that one or more of your hemlock trees is infested with hemlock woolly adelgid, consider treating them with a systemic insecticide. Johnson, W.T. The male cover is elongate, white, and about 1.5 mm long. View our privacy policy. This insect is typically found on the underside of needles and therefore may be difficult to detect. Symptoms the host tree experiences include: 1) were accidentally introduced into the vicinity of New York City from Japan at the turn Of this century and have subsequently spread into several northeastern states (Weiss 1914, Ferris 1936). They feed, with their tube-like mouthparts, within the vascular system, where nutrients and fluids are transported. Elongate hemlock scale has a piercing-sucking mouthpart, which it uses to feed on cell contents within conifer needles. Safari) is very effective in suppressing elongate hemlock scale and will have less of an impact on the bio-allies if applied as a trunk application or soil drench. Elongate hemlock scale, Fiorinia externa Ferris, an invasive scale in the USA, is native to Japan and China that is a pest of eastern hemlock (Tsuga canadensis [L.] Carrière) in the eastern United States. The elongate hemlock scale (Fiorinia externa) is native to Japan and was first detected in the US in Queens, New York over a century ago. The principal host plants include eastern hemlock, T. canadensis, Carolina hemlock, T. caroliniana, and northern Japanese hemlock, T. diversifolia , fir, Abies spp., and spruce, Picea spp. 566 pp. A heavy infestation of elongate hemlock scales. Elongate Hemlock Scale is an exotic scale insect that prefers hemlock, spruce and fir but will also feed on cedar, pine, and yew. Insects That Feed on Trees and Shrubs. LEARN HOW TO STOP THE INVASIVE SPOTTED LANTERNFLY, Coronavirus: Information and resources for the Extension Community, Save For Later Print Available in Spanish, Eric R. Day, Virginia Polytechnic Institute and State University, Bugwood.org. Though commonly associated with hemlocks, EHS can feed on many species of conifers including firs, pines, spruces, cedars, and Douglas fir. Although Eastern hemlock is most heavily damaged, heavy infestations also build up on Carolina hemlock, Japanese hemlock, yews, spruces, and firs. Immature scale (crawlers) are green to yellow. But they’re all sap-sucking invaders who can spread a wide variety of plant diseases, and nobody wants to discover them on their plants! If the adelgid is not controlled, infested trees will decline and eventually die, usually within four to 10 years. Elongate hemlock scale—sometimes referred to as Fiorinia scale—is an armored scale found more prevalently in southeastern Pennsylvania. Excessive loss of plant fluid reduces the growth and health of the plant. Short-lived populations in Ontario have been identified and eliminated. Research has demonstrated that nitrogen fertilization of hemlocks enhanced population increases of this armored scale. Ew, scale insects! Heavy infestations can have significant impacts on conifers. Cultural practices that reduce moisture stress and promote general tree health may prolong survival. In addition to HWA, Safari also controls elongate hemlock scale, another common pest to hemlock trees. Many of them are agricultural pests, while others prey on trees or other plant life. This injury causes needles to drop prematurely giving the crown of an infested tree a thin appearance. It occurs in many states in the eastern U.S., including Pennsylvania. Hemlock scale feeds on the undersides of the needles of several species of trees. Control of the elongate hemlock scale using sprays is complicated by two factors: With the exception … Elongate Hemlock Scale (Fiorinia externa) Fiorinia externa, also referred to as elongate hemlock scale or fiorina scale, is an insect native to Japan that infests eastern hemlock, northern Japanese hemlock, Carolina hemlock, fir, and spruce. Translucent, oval eggs occur beneath the scale covering of the female. Crawlers settle on the underside of the needle, insert their mouthparts, feed for three to four weeks, and then molt into second instar nymphs. Hemlock trees are a ‘foundation species’ of forests. The waxy covers of this species can be observed on the lower needle surface as well as on new cones. Use Insecticides With Care. Scales injure host plants by inserting their threadlike, piercing-sucking mouthparts into needles and withdraw vital nutrients necessary for plant growth from mesophyll cells. When closely examining infested hemlock needles, adult males may look like tiny wasp parasitoids as they crawl across the needles. Adult scale are round to oval, dark gray or black, and about 2 mm (0.1 inch) in diameter. REC, Western Maryland 1978, Diseases & Pests of Ornamental Plants, 5th Ed. In general, avoid using contact insecticides as much as possible as they will often kill the naturally occurring enemies of scale insects. REC, Lower Eastern Shore Other pests and issues aside from HWA can affect the health of hemlocks; however, as HWA is the hemlock pest most likely to cause tree mortality, this document only addresses HWA chemical treatments. Signs of elongate hemlock scale include a yellow banding on the top of infested needles which can lead to premature needle drop. Elongate hemlock scale (EHS) is primarily found infesting eastern hemlock (Tsuga canadensis) and Carolina hemlock (Tsuga caroliniana), along with fir and spruce in Massachusetts. Photographer: Eric R. Day Virginia Polytechnic Institute and State University. The first choice to make is whether to use a systemic or non-systemic type of treatment, and there are quite a few products to choose from in each category. These less preferred host plants, if infested, are usually growing adjacent to infested hemlocks. The hemlock woolly adelgid (scientific name Adelges tsugae) was first reported in the Eastern United States in the state of Virginia in 1951, where it was likely brought in on infested nursery stock from Japan. The crowns of infested trees may … Elongate hemlock scale may also be observed on cedar, Douglas-fir, pine, and yew, which tend to grow adjacent to infested hemlocks. Why do we need this? Pirone, P.P. Be sure the product you select is labeled for treating adelgids. Scale typically are found as small bumps on the underside of needles. There are several key insect and mite pest species that feed on hemlock foliage. The elongate hemlock scale, Fiorinia externa Ferris, and a circular hemlock scale, Nuculaspis tsugae (Marlatt), (Fig. Populations of HWA are also found in western North America, including Canada, where it has most likel… Author: Mary Kay Malinoski, University of Maryland Extension Specialist, Home and Garden Information Center (retired)and John Davidson, Extension Entomologist, University of Maryland (retired). When this condition is present, it may cause uninformed individuals to misdiagnose this as hemlock woolly adelgid. When closely examining infested hemlock needles, adult males may look like tiny wasp parasitoids as they crawl across the needles. Elongate hemlock scale is an armored scale, non-native to the United States and first observed in New York in 1908. Safari Insecticide is a new generation, super-systemic neonicotinoid with quick uptake and knockdown of HWA and a broad spectrum of other major landscape and ornamental pests. Elongate hemlock scale (Fiorinia externa) is another non-native insect pest of eastern hemlock in the U.S. New York: John Wiley & Sons. Effective timing includes spring applications before bud-break or … This invasi… In three to four weeks eggs hatch into first instar nymphs called crawlers that migrate to new needles on the same plant. It may also be found in cedar, Douglas fir, pine, and yew when those plants are grown nearby an infested hemlock. Individuals that develop from these eggs mature and overwinter. There is an abundance of crawlers from late May through early June. When they settle to feed, the crawlers lose their legs and excrete an amber-colored, oval covering. 1991. The elongate hemlock scale female, which would normally be seen if an infestation is present, is dark brown, longer than wide, and typically found on the underside of the needles. In early spring the females deposit eggs beneath their waxy covers and may continue to lay eggs through early summer. There are many crawlers from May through June. 1967, Stimmel 1980). Get notified when we have news, courses, or events of interest to you. The hemlock woolly adelgid (HWA) is an invasive insect pest that affects eastern and Carolina hemlock trees. The females and eggs are protected by a hard, waxy covering. The scale covers are waxy and may be so numerous that the needles have a whitewashed appearance. As of May 2017, hemlock woolly adelgid (also referred to as HWA) had been found in localized areas of Allegan, Muskegon, Oceana and Ottawa counties, and additional surveys are underway. The adult female's body beneath the waxy cover, eggs, and crawler stage are yellow. The elongate hemlock scale, sometimes known as the fiorinia scale, is a serious armored scale insect pest on ornamental and forest hemlock trees in Pennsylvania. Scales rarely kill a plant by themselves but may predispose plants to attack from wood-boring insects or open up wounds that provide entry sites for plant pathogens. Authored by: Gregory A. Hoover, Sr. Extension Associate. The flattened, elongate, light yellow brown to brownish orange waxy cover of the adult female is about 1.5 mm long. Another four weeks is required to reach maturity. Scale insect numbers increase more slowly on healthy trees compared to trees under stress. Mated females start to lay second-generation eggs six to eight weeks after mating. Armored scale insects do not feed on the contents of vascular cells. The scale has long-lived adult females that reproduce slowly over much of the year, leading to a population with highly overlapping life stages. This type of treatment is highly effective on 95-99% of the pests as they ingest an ingredient t… REC, Dogwood Insect Pests: Identification and Management, Flowering Dogwood Trees: Selection, Care, and Management of Disease Problems, Why Are Leyland Cypress Trees Turning Brown, Azaleas and Rhododendrons: Common Diseases and Abiotic Problems, Boxwood: Preventing and Managing Common Pests and Diseases, Diagnosing Problems of Azaleas and Rhododendrons, Ornamental Fruit Trees: Preventing, Diagnosing, and Managing Problems. Effective management of this key pest is extremely difficult since all stages of development may be present during the growing season. and H.H. The flattened, elongate, light yellow brown to brownish orange waxy cover of the adult female is about 1.5 mm long. Two small wasp parasitoids, the lady beetle, Chilocorus stigma, and several species of lacewings are natural enemies of this scale insect that provide some population reduction. Hemlock woolly adelgid is established in isolated locations in the western Lower Peninsula of Michigan. Introduction The elongate hemlock scale (Fiorinia externa), is an introduced pest from Asia. Ithaca, NY: Comstock Publishing Associates, Cornell University Press. It was first observed in Queens, New York in 1908. Most contact insecticides cannot penetrate the waxy covering on scale nymphs and adults, so the crawler stage is the only life stage that these insecticides control. In western North Carolina, hemlocks and true firs including Fraser fir are its most common hosts. The adult female's body beneath the waxy cover, eggs, and crawler stage are yellow. Elongate hemlock scale outbreaks may increase after a tree has been infested with hemlock woolly adelgid, drought, or other stresses. However, these insects are very hard to detect. Dispersal of crawlers over large distances usually occurs by wind currents or on the feet or plumage of birds. This is an ideal time to treat with a registered insecticide formulation applied according to label directions. Like other armored scales, it does not feed in the vascular tissue. Bait treatments and insecticides can be used to control ants in the outside nest. Soil-injected systemic insecticides used to manage hemlock woolly adelgid are not effective in managing this species of armored scale insect. two armored scale insects from Asia. In cases were elongate hemlocks scale is more prevalent this can be a good alternative or supplement to a spray program. Whether flat against leaves or fruit, or lumpy bumps on branches or stems, this widespread superfamily of insects is well over 8000 species strong. A 2% summer rate of horticultural oil may be applied to control crawlers in the summer (June and August), although do not spray if temperatures are above 85 degrees F. This may not be as effective in controlling the elongate hemlock scale,Fiorinia externa. Scale insects are common insect pests on ornamental trees and shrubs in landscapes. DCNR has been releasing a biological control agent for elongate hemlock scale, as well as using a systemic insecticide to reduce … As with most other armored scales, elongate hemlock sc… Elongate Hemlock Scale- Beyond Pest Control is a fast reliable pest control company, We've been in the business since 1971. By entering your email, you consent to receive communications from Penn State Extension. Pesticides are poisonous. Scale insects are small pests that feed on hemlock trees, and cause a waxy substance to transfer to hemlock needles, giving them a mosaic appearance. One female may produce a total of 20 eggs in a lifetime. Read the Label. The Minnesota Department of Agriculture is advising people who have purchased wreaths, boughs and other evergreen decorations this season to burn them or … Adult male scales only have one pair o… See All Pest, Disease and Weed Identification, See All Beer, Hard Cider, and Distilled Spirits, See All Community Planning and Engagement. The covers of the adult females are elongated, oval and translucent to light brown. Like hemlock woolly adelgid, elongate hemlock scale is a sap feeder, which also can cause tree decline and mortality. Elongate hemlock scale may also be observed on cedar, Douglas-fir, pine, and yew, which tend to grow adjacent to infested hemlocks. The insect damages hemlock needles by inserting needle-like mouth parts into leaf tissue and removing cell fluids. Management may be difficult with contact insecticides for this pest since the life stages overlap throughout the growing season. Hemlocks contribute to watershed quality and provide a unique micro-environment with a cool habitat for many species of birds, insects, and mammals. Hemlock Woolly Adelgid is a small wingless insect which has piercing mouthparts to feed in the xylem of the small hemlock twigs. New York: John Wiley & Sons. Read and follow directions and safety precautions on labels. When mature, males emerge as tiny winged insects, mate with the female, and then die. An infestation of this armored scale weakens trees allowing successful attack by secondary organisms such as the hemlock borer, Phaenops fulvoguttata, or Armillaria root rot. We embody the University's land-grant mission with a commitment to eliminate hunger, preserve our natural resources, improve quality of life, and empower the next generation through world-class education. JavaScript seems to be disabled in your browser. Sometimes waxy secretions from settled crawlers may build into a mass of tangled strands. It's important to accurately identify what pest species or causal organism is present when maintaining the health of hemlocks. To control any of the above scale insects, a 3% dormant rate of horticultural oil may be applied in late February to early March, or before budbreak in the early spring. This insect is originally from Asia and was first discovered in Portsmouth in 2000. This species overwinters as fertilized females or eggs. Though systemic insecticides in the class of neonicotinoids can be harmful to bees, when applied to the trunk of the tree, exposure is limited. Closeup of elongate hemlock on needlesPhoto: Eric R. Day, Virginia Polytechnic Institute and State University, Bugwood.org. Fiorinia externa, also referred to as elongate hemlock scale or fiorina scale, is an insect native to Japan that infests eastern hemlock, northern Japanese hemlock, Carolina hemlock, fir, and spruce. Follow All Safety Precautions. You must have JavaScript enabled in your browser to utilize the functionality of this website. Central Maryland Scale feed on the needles by sucking … Mention of trade names in this publication does not constitute an endorsement by the University of Maryland Extension. Adult females are soft-bodied, legless, wingless, and are enclosed in an elongate cover that is light yellow to brown, translucent, and about 2 mm long. ■ Systemic materials are absorbed by the tree and transported upward into the plant where they are ingested by the target pest. The elongate hemlock scale (also known as EHS) that hitched a ride to Minnesota likely came from a processor in North Carolina, where the invasive insect has long been a problem. A second spray should be applied in early July, if needed. The elongate hemlock scale is in a group of insects called “armored scales”. Adult male scales only have one pair of wings. The white, waxy cover of the male is smaller. The waxy covers of this species can be observed on the lower needle surface as well as on new cones. Dispose of empty containers right away, in a safe manner and place. Spraying of large trees is very difficult at best. The scale is only known to feed on Canada balsam fir ( Abies canadensis ), grand fir ( Abies grandis ), Colorado blue spruce ( Picea pungens ), douglas fir ( Pseudotsuga taxifolia ), eastern hemlock ( Tsuga canadensis ), and western hemlock ( Tsuga heterophylla ). This pest occurs in Connecticut, Maryland, Massachusetts, New Jersey, New York, Ohio, Rhode Island, and Virginia. Since that time, EHS has spread to 15 states in the eastern US. Adult females may live up to one year. Egg production and crawler emergence continues for another generation. This key pest also feeds on cedar, Cedrus spp., Douglas-fir, Pseudotsuga menziesii, pine, Pinus spp., and yew, Taxus spp., but these are not preferred hosts. They are long-living, shade tolerant conifers that usually grow in groups or are assembled with other tree species. Maintaining healthy trees may reduce the chances of an increase in the population of this pest. Male covers are similar but smaller. It has since spread and is now found in the east from northern Georgia to coastal Maine and southwestern Nova Scotia. Elongate hemlock scale on hemlock needles: Elongate hemlock scale on hemlock (left, middle (adelgid circled)) and fir (right): Needle discoloration on hemlock (left) and fir (right): Note: other pathogens, pests and processes will cause needle yellowing. They mate and the fertilized female produces eggs under her scale cover. Drought stress and over-fertilizing with nitrogen contribute to scale insect population increase. The overlap of these generations produces needle scales throughout the summer. The elongate hemlock scale, sometimes known as the fiorinia scale, is a serious armored scale insect pest of hemlock, Tsuga spp., on ornamental and forest trees in Pennsylvania. Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. The pale yellow crawlers are about 1⁄250 inch (0.1 mm) long and have six short legs. There, EHS primarily preys on the eastern hemlock (Tsuga canadensis) that dot those Atlantic/Appalachian states. Elongate hemlock scale undergoes one to two overlapping generations per year with more generations occurring in warmer climates (Talerico et al. Arborist Advice Elongate Hemlock Scale is a species of scale insects that is armored with a hard, waxy covering. 560 pp.Pirone, P.P. Repeat applications may need to be made for effective crawler management until mid-September. 1978, Diseases & Pests of Ornamental Plants, 5th Ed. Originally from Japan, it was first discovered in the United States in Long Island, New York in 1908. Frequently, this key pest is found on the same hemlock tree with hemlock woolly adelgid, Adelges tsugae. These waxy strands may be so abundant that it gives the lower surface of infested needles a white appearance. The systemic insecticide dinotefuran (e.g. There are several options available to homeowners to treat HWA. Elongate hemlock scale infestation on hemlock. The white, waxy cover of the male is smaller. It is believed that this armored scale insect was unintentionally introduced into the United States from Japan. Under the SLN label, Safari should be applied as a basal trunk spray at a rate of 9.0 oz per gallon of water. Lyon. Male and female scales develop differently and have different protective coverings. Feeding injury causes needles to develop yellow banding on the top of infested needles. 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