hemlock woolly adelgid

Insects: Piercing and Sucking Insects
Hexapoda (including Insecta) > Hemiptera > Adelgidae > Adelges tsugae Annand
Hemlock woolly adelgid (HWA) is native to Japan and possibly China. It was first observed in western North America in the early 1920's and had moved east to Virginia by the 1950's. In the eastern United States, HWA is now found from northern Georgia, north along the Appalachian Mountains to southern New England. Movement of live infested hemlocks, wind, birds, and mammals disperse it on a local scale. Hosts include forest and ornamental hemlock trees (Tsuga spp.). HWA is a serious pest of eastern hemlock and Carolina hemlock. Size varies from 1/16 to 1/8 of an inch in length with piercing/ sucking mouthparts. All adults are female with each female producing 50-300 eggs in a lifetime. It produces increasing amounts of white, woolly wax used to protect itself and its eggs. A sign of infestation is the presence of what appears to be the tips of cotton swabs on the bases of needles. Needle loss and twig desiccation, caused by the insects feeding, hinders shoot growth. Needle loss is followed by twig die-back, defoliation, and death, usually within four to six years of infestation. Severe infestations can eliminate the hemlock component from forest stands.

117 records

<View Images as Host>

<View Thumbnails>

Image Descriptor Description Photographer
1276003 Adult(s) With wax removed Michael Montgomery
1380194 Adult(s) Chris Evans
1523054 Adult(s) Daniel Herms
1510011 Adult(s) closeup Rusty Rhea
3225077 Adult(s) Connecticut Agricultural Experiment Station Archive
5017089 Biological Control Biological Control Beetle release in Pennsylvania Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
1344024 Control Spraying insecticidal soap using a slip-on unit on an ATV Great Smoky Mountains National Park Resource Management Archive
1344025 Control Spraying insecticidal soap Great Smoky Mountains National Park Resource Management Archive
5022094 Control suppression, 2005 Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5022095 Control Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5022096 Control Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5023002 Control Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5027034 Control treatment with Ima-Jet system using imidachloprid Richard Turcotte
1344018 Control Using a backpack sprayer and insecticidal soap for hemlocks Great Smoky Mountains National Park Resource Management Archive
1344045 Control Stem injections of a systemic insecticide Great Smoky Mountains National Park Resource Management Archive
1344047 Control Tree injection Great Smoky Mountains National Park Resource Management Archive
1344053 Control Soil injection of imidacloprid Great Smoky Mountains National Park Resource Management Archive
1344056 Control Soil drenching hemlocks with imidacloprid Great Smoky Mountains National Park Resource Management Archive
1344057 Control Soil drenching hemlocks with imidacloprid Great Smoky Mountains National Park Resource Management Archive
1344061 Control Marking a hemlock that has been treated by soil drenching Great Smoky Mountains National Park Resource Management Archive
1344064 Control Raking leaf litter and loam away from a hemlock, so it can be treated by soil drenching Great Smoky Mountains National Park Resource Management Archive
1344065 Control Soil injection of imidacloprid around hemlock Great Smoky Mountains National Park Resource Management Archive
1276005 Control Tree removal Michael Montgomery
1294054 Control An insecticidal soap used to treat infested hemlocks. Great Smoky Mountains NP, TN Great Smoky Mountains National Park Resource Management Archive
1294055 Control An insecticidal soap used to treat infested hemlocks. Great Smoky Mountains NP, TN Great Smoky Mountains National Park Resource Management Archive
1344002 Control Spraying insecticidal soap Great Smoky Mountains National Park Resource Management Archive
1344003 Control Spraying insecticidal soap Great Smoky Mountains National Park Resource Management Archive
1344005 Control Spraying insecticidal soap Great Smoky Mountains National Park Resource Management Archive
1344006 Control Spraying insecticidal soap Great Smoky Mountains National Park Resource Management Archive
1344008 Control Spraying insecticidal soap Great Smoky Mountains National Park Resource Management Archive
1344010 Control Spraying insecticidal soap Great Smoky Mountains National Park Resource Management Archive
1344011 Control Spraying insecticidal soap Great Smoky Mountains National Park Resource Management Archive
1344012 Control Soil drenching with imidicloprid, a systemic insecticide Great Smoky Mountains National Park Resource Management Archive
1344013 Control Marking a hemlock with spray paint, to signify that it has been treated with imidacloprid Great Smoky Mountains National Park Resource Management Archive
1344014 Control Taking the DBH of a hemlock, to calculate how much imidacloprid it will take to treat it. Great Smoky Mountains National Park Resource Management Archive
1344121 Control Tree IV for systemic insecticide Great Smoky Mountains National Park Resource Management Archive
1344125 Control Tree IV Great Smoky Mountains National Park Resource Management Archive
1344127 Control Tree IV (showing that in can be safely used close to water, where no other chemical treatment can be used) Great Smoky Mountains National Park Resource Management Archive
1344137 Control Tree IV plug that remains in place once injection treatment is finished Great Smoky Mountains National Park Resource Management Archive
1344138 Control Tree IV injector Great Smoky Mountains National Park Resource Management Archive
1344143 Control Tree IV Great Smoky Mountains National Park Resource Management Archive
1344146 Control Tree IV Great Smoky Mountains National Park Resource Management Archive
1344147 Control Tree IV Great Smoky Mountains National Park Resource Management Archive
1344148 Control Tree IV Great Smoky Mountains National Park Resource Management Archive
1344150 Control Marking a hemlock that has been treated by Tree IV Great Smoky Mountains National Park Resource Management Archive
5125061 Damage Showing damage resulting from 2-3 year old infestation. See image #1346067 for image of 1 year old infestation. Chris Evans
5125062 Damage Showing damage resulting from a 2-3 year old infestation. See image #1346067 for image of 1 year old infestation. Chris Evans
5125063 Damage Damage resulting from a 2-3 year old infestation. Chris Evans
5125064 Damage Showing sparse, shortened foliage. Chris Evans
5125065 Damage Showing damage resulting from 2-3 year old infestation. Chris Evans
5125066 Damage Showing damage resulting from 2-3 year old infestation. Chris Evans
2167018 Damage Infested foliage William M. Ciesla
2167019 Damage Infested foliage, William M. Ciesla
2167023 Damage Infested foliage William M. Ciesla
1520084 Damage HWA on hemlock needles USDA Forest Service - Region 8 Archive
5018078 Egg(s) Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5395117 Egg(s) Shimat Joseph
5395118 Egg(s) Shimat Joseph
1344028 Equipment Spray Unit used for hemlock trees, up to around 80 ft. tall. Great Smoky Mountains National Park Resource Management Archive
1510054 Equipment Ground spray equipment used for control of balsam woolly adelgid, Mt. Mitchell State Park, NC, ca 1961. William M. Ciesla
1344080 Equipment ATV spray unit used for treating hemlocks with soap Great Smoky Mountains National Park Resource Management Archive
1344020 Equipment Slip-on spray unit used to treat hemlocks up to around 50 ft. Great Smoky Mountains National Park Resource Management Archive
5018072 Feature(s) no new growth Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5018073 Immature(s) crawler Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5018069 Infestation Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5018075 Infestation Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
5018076 Infestation Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
1520081 Infestation USDA Forest Service - Region 8 Archive
1520082 Infestation USDA Forest Service - Region 8 Archive
1520083 Infestation HWA on hemlock needles USDA Forest Service - Region 8 Archive
1276004 Infestation Recently infested Michael Montgomery
1380195 Infestation Chris Evans
1380196 Infestation Chris Evans
1380197 Infestation Chris Evans
1626009 Infestation Underneath the wax, adelgids resemble tiny, plump aphids without cornicles. John A. Weidhass
1748045 Infestation Robert L. Anderson
1748046 Infestation Robert L. Anderson
1748047 Infestation Robert L. Anderson
1748048 Infestation thinning of crown Robert L. Anderson
1748049 Infestation Robert L. Anderson
2110026 Infestation Photo taken in Rabun County, Georgia James Johnson
2110027 Infestation Photo taken in Rabun County, Georgia James Johnson
2110028 Infestation Photo taken in Rabun County, Georgia James Johnson
2110029 Infestation Photo taken in Rabun County, Georgia James Johnson
2110030 Infestation Photo taken in Rabun County, Georgia James Johnson
2110031 Infestation Photo taken in Rabun County, Georgia James Johnson
2110033 Infestation Photo taken in Rabun County, Georgia James Johnson
2110034 Infestation Photo taken in Rabun County, Georgia James Johnson
2110035 Infestation Photo taken in Rabun County, Georgia James Johnson
2167010 Infestation Decline and mortality caused by hemlock wolly adelgid, William M. Ciesla
2167011 Infestation Decline and mortality William M. Ciesla
2167012 Infestation Decline and mortality, William M. Ciesla
2167013 Infestation Decline and mortality William M. Ciesla
2167014 Infestation William M. Ciesla
2167015 Infestation Decline and mortality William M. Ciesla
2167016 Infestation Infested foliage William M. Ciesla
2167017 Infestation Infested foliage William M. Ciesla
1346067 Infestation Chris Evans
1346068 Infestation Chris Evans
1346069 Infestation Chris Evans
1346070 Infestation Chris Evans
1346071 Infestation Chris Evans
1346072 Infestation Chris Evans
1380192 Infestation Chris Evans
1380193 Infestation Chris Evans
1293001 Infestation Adelgids feed near the base of hemlock needles. Photo taken in lab at Clemson University - sample from Oconee County, SC. James Johnson
1293002 Infestation Photo taken in lab at Clemson University - sample from Oconee County, SC. James Johnson
1293003 Infestation Pale crown appearance with no new growth indicate this tree is under severe attack from Hemlock Woolly Adelgids. Photo taken in Rabun County, Georgia James Johnson
1293010 Infestation Crown dieback on hemlock is the result of at least 2 years of attack from hemlock woolly adelgid. Photo taken in Rabun County, Georgia. James Johnson
0355015 Infestation Robert L. Anderson
0488055 Infestation John H. Ghent
0718057 Infestation John A. Weidhass
1276001 Infestation Ovisacs on the underside of a branch Michael Montgomery
5018074 Larva(e) Newly settled larvae Pennsylvania Department of Conservation and Natural Resources - Forestry Archive
1276002 Life Cycle Adult and eggs inside an ovisac Michael Montgomery
1344016 Survey Tree climbing old growth hemlocks to check for adelgids and predatory beetles Great Smoky Mountains National Park Resource Management Archive
1344017 Survey Tree climbing old growth hemlocks to check for adelgids and predatory beetles Great Smoky Mountains National Park Resource Management Archive


footer line
USDA Forest Service The Bugwood Network University of Georgia

Home | Image Usage | Accessibility Policy | Privacy Policy | Disclaimers | Contact Us

Last updated on Monday, August 11, 2008 at 03:12 PM
www.insectimages.org version 2.0, XHTML 1.1, CSS, 508.