Use Insecticides With Care. Translucent, oval eggs occur beneath the scale covering of the female. Excessive loss of plant fluid reduces the growth and health of the plant. Immature scale (crawlers) are green to yellow. Ew, scale insects! Why do we need this? REC, Lower Eastern Shore This pest occurs in Connecticut, Maryland, Massachusetts, New Jersey, New York, Ohio, Rhode Island, and Virginia. Elongate hemlock scale (Fiorinia externa) is another non-native insect pest of eastern hemlock in the U.S. Females have three developmental life stages after the egg, and males have five. Elongate hemlock scale infestation on hemlock. The scale covers are waxy and may be so numerous that the needles have a whitewashed appearance. 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. Dispersal of crawlers over large distances usually occurs by wind currents or on the feet or plumage of birds. By entering your email, you consent to receive communications from Penn State Extension. 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. It was first observed in Queens, New York in 1908. DCNR has been releasing a biological control agent for elongate hemlock scale, as well as using a systemic insecticide to reduce … Hemlock scale feeds on the undersides of the needles of several species of trees. They feed, with their tube-like mouthparts, within the vascular system, where nutrients and fluids are transported. Signs of elongate hemlock scale include a yellow banding on the top of infested needles which can lead to premature needle drop. See All Pest, Disease and Weed Identification, See All Beer, Hard Cider, and Distilled Spirits, See All Community Planning and Engagement. 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. Perhaps the biggest pest of Hemlock trees is the Hemlock woolly adelgid. 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. The hemlock woolly adelgid (HWA) is an invasive insect pest that affects eastern and Carolina hemlock trees. As with most other armored scales, elongate hemlock sc… Johnson, W.T. Soil-injected systemic insecticides used to manage hemlock woolly adelgid are not effective in managing this species of armored scale insect. They are long-living, shade tolerant conifers that usually grow in groups or are assembled with other tree species. 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 ). 560 pp.Pirone, P.P. Research has demonstrated that nitrogen fertilization of hemlocks enhanced population increases of this armored scale. This insect is originally from Asia and was first discovered in Portsmouth in 2000. The elongate hemlock scale, Fiorinia externa Ferris, and a circular hemlock scale, Nuculaspis tsugae (Marlatt), (Fig. Drought stress and over-fertilizing with nitrogen contribute to scale insect population increase. Effective timing includes spring applications before bud-break or … 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. The white, waxy cover of the male is smaller. 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. Scale insect numbers increase more slowly on healthy trees compared to trees under stress. Though commonly associated with hemlocks, EHS can feed on many species of conifers including firs, pines, spruces, cedars, and Douglas fir. The scale has long-lived adult females that reproduce slowly over much of the year, leading to a population with highly overlapping life stages. Male covers are similar but smaller. Adult females may live up to one year. 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. Scale feed on the needles by sucking … You must have JavaScript enabled in your browser to utilize the functionality of this website. Armored scale insects do not feed on the contents of vascular cells. It's important to accurately identify what pest species or causal organism is present when maintaining the health of hemlocks. Control of the elongate hemlock scale using sprays is complicated by two factors: With the exception … Pesticides are poisonous. Pest description and damage Hemlock scale feed on the needles of Eastern hemlock (Tsuga canadensis) and spruces (especially Colorado blue). 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 adult female's body beneath the waxy cover, eggs, and crawler stage are yellow. Hemlock woolly adelgid is established in isolated locations in the western Lower Peninsula of Michigan. Frequently, this key pest is found on the same hemlock tree with hemlock woolly adelgid, Adelges tsugae. Adult male scales only have one pair of wings. Hemlock Trees and their Pests. Scale insects are common insect pests on ornamental trees and shrubs in landscapes. The adult female's body beneath the waxy cover, eggs, and crawler stage are yellow. 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. Maintaining healthy trees may reduce the chances of an increase in the population of this pest. Elongate hemlock scale (EHS) is primarily found infesting eastern hemlock (Tsuga canadensis) and Carolina hemlock (Tsuga caroliniana), along with fir and spruce in Massachusetts. The overlap of these generations produces needle scales throughout the summer. If the adelgid is not controlled, infested trees will decline and eventually die, usually within four to 10 years. 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