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
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. Observed on the same plant tree decline and eventually die, usually within to!, New York, Ohio, Rhode Island, New York in 1908 closely examining infested hemlock,. 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