Elongate hemlock scale outbreaks may increase after a tree has been infested with hemlock woolly adelgid, drought, or other stresses. 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. Elongate hemlock scale may also be observed on cedar, Douglas-fir, pine, and yew, which tend to grow adjacent to infested hemlocks. Ithaca, NY: Comstock Publishing Associates, Cornell University Press. It is believed that this armored scale insect was unintentionally introduced into the United States from Japan. and H.H. Consider having a licensed arborist do the sprayi… 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. Control of the elongate hemlock scale using sprays is complicated by two factors: With the exception … Photographer: Eric R. Day Virginia Polytechnic Institute and State University. The white, waxy cover of the male is smaller. Elongate Hemlock Scale is an exotic scale insect that prefers hemlock, spruce and fir but will also feed on cedar, pine, and yew. When mature, males emerge as tiny winged insects, mate with the female, and then die. 1967, Stimmel 1980). Like other armored scales, it does not feed in the vascular tissue. Male and female scales develop differently and have different protective coverings. The male cover is elongate, white, and about 1.5 mm long. The covers of the adult females are elongated, oval and translucent to light brown. Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. The hemlock woolly adelgid (HWA) is an invasive insect pest that affects eastern and Carolina hemlock trees. Scale feed on the needles by sucking … Adult male scales only have one pair o… 1991. In western North Carolina, hemlocks and true firs including Fraser fir are its most common hosts. Central Maryland By entering your email, you consent to receive communications from Penn State Extension. The scale covers are waxy and may be so numerous that the needles have a whitewashed appearance. The scale has long-lived adult females that reproduce slowly over much of the year, leading to a population with highly overlapping life stages. Hemlocks contribute to watershed quality and provide a unique micro-environment with a cool habitat for many species of birds, insects, and mammals. In three to four weeks eggs hatch into first instar nymphs called crawlers that migrate to new needles on the same plant. The insect damages hemlock needles by inserting needle-like mouth parts into leaf tissue and removing cell fluids. This is an ideal time to treat with a registered insecticide formulation applied according to label directions. When this condition is present, it may cause uninformed individuals to misdiagnose this as hemlock woolly adelgid. Use Insecticides With Care. The pale yellow crawlers are about 1⁄250 inch (0.1 mm) long and have six short legs. 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 injure host plants by inserting their threadlike, piercing-sucking mouthparts into needles and withdraw vital nutrients necessary for plant growth from mesophyll cells. Immature scale (crawlers) are green to yellow. Adult male scales only have one pair of wings. 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. Do not contaminate forage, streams, or ponds. Read the Label. When they settle to feed, the crawlers lose their legs and excrete an amber-colored, oval covering. Authored by: Gregory A. Hoover, Sr. Extension Associate. Whether flat against leaves or fruit, or lumpy bumps on branches or stems, this widespread superfamily of insects is well over 8000 species strong. 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. ■ Systemic materials are absorbed by the tree and transported upward into the plant where they are ingested by the target pest. Bait treatments and insecticides can be used to control ants in the outside nest. Perhaps the biggest pest of Hemlock trees is the Hemlock woolly adelgid. Spraying of large trees is very difficult at best. DCNR has been releasing a biological control agent for elongate hemlock scale, as well as using a systemic insecticide to reduce … The adult female's body beneath the waxy cover, eggs, and crawler stage are yellow. Excessive loss of plant fluid reduces the growth and health of the plant. Repeat applications may need to be made for effective crawler management until mid-September. These waxy strands may be so abundant that it gives the lower surface of infested needles a white appearance. This injury causes needles to drop prematurely giving the crown of an infested tree a thin 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. 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. 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