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Identification Resources

Provides general resources to help identify unknown species that may be invasive. Species identification is important in helping gardeners, land managers, and landscape architects identify invasive species that can be harmful to local habitats. Resources are organized alphabetically by organization.

An important caveat is it can be difficult to identify species properly on the Internet. If you are unable to identify the species in question, you may want to contact your county Extension office and work with Extension personnel to obtain assistance from an area agent or state specialist (select state to see state pest detection contacts). Or, you may want to use the Ask an Expert feature of eXtension - Invasive Species.

See other sections for species specific information:

Busting Bugs: USDA Creates Online Tools to ID Pests (Aug 14, 2013)
USDA. Blog.
ID Tools helps agency staff to quickly identify pests, including insects, diseases, harmful weeds, and more, through an efficient, online database system. ID Tools currently includes more than 30 websites covering a vast array of pests and pests associated with specific commodities.

Identification Resources: Insects, Plants & Diseases
University of Florida. Cooperative Extension.
Many Florida residents find unknown plants growing in their yard, unknown bugs in their houses or gardens, and apparent diseases on what were previously healthy plants. But Florida residents may not know what resources are available to identify these disease, plant, and pest organisms.


Species Identification Tools

Insect & Spider Identification
New Hampshire Department of Agriculture, Markets & Food.

North American Invasive Identification Guide and Checklist and IDnature Guides
University of Georgia. Discover Life.

Identification Resources: Insects, Plants & Diseases
University of Florida. Cooperative Extension.

Landscape Problem Solver
University of Maryland. Maryland Cooperative Extension.
Identifies plant pests, including insects and diseases. Includes information and instructions for submitting plant or insect samples (PDF | 70 KB).

Identification Aids Services
USDA. Animal and Plant Health Inspection Service.
Recommended resources for those seeking identification assistance. Please note that any individual who believes they have encountered an invasive species or other quarantine significant pest, is encouraged to contact their local Cooperative Extension Office for verification.

Digital Identification Tools
USDA. APHIS. PPQ. CPHST. Identification Technology Program.
"ITP supports PPQ in its efforts to prevent the entry, spread, and establishment of invasive pests in the U.S. by delivering interactive, electronic identification tools."

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Aquatic Species

Marine Invasive Species Identification Guide for the Puget Sound Area: Puget Sound Marine Invasive Species Volunteer Monitoring Program (MISM) (Jul 2009; PDF | 1 MB)
Puget Sound Partnership (Washington).

Marine Introduced Species Monitoring Resource Center - Species Identification
Salem Sound Coastwatch (Massachusetts; Gulf of Maine).
Also see - New England Marine Invaders Identification and Potential Marine Invaders Identification

Aquatic Animals

Identifying Michigan Fish (including Snakehead)
Michigan Department of Natural Resources and Environment.

Asian Carp Key to Identification (PDF | 113 KB)
Mississippi Interstate Cooperative Resource Association.

Brief Guide to Crayfish Identification in the Pacific Northwest (2009; PDF | 440 KB)
University of Washington. School of Aquatic and Fishery Science.

How to Identify a Mitten Crab (PDF | 198 KB)
Aquatic Nuisance Species Task Force.

Wisconsin Fish Identification
University of Wisconsin Center of Limnology; Wisconsin Sea Grant; Wisconsin Department of Natural Resources.

Aquatic Plants

Connecticut's Invasive Aquatic and Wetlands Plants Identification Guide (2010; PDF | 8.4 MB)
Connecticut Agricultural Experiment Station.
Bulletin No. 1027.

Aquatic Invasive Plant Identification Guide
River to River Cooperative Weed Management Area (Illinois).

A Field Guide to Invasive Plants of Aquatic and Wetland Habitats for Michigan (2010; PDF | 4.2 MB)
Michigan State University Extension.

Training - Species Identification
Michigan State University. Midwest Invasive Species Information Network.
The invasive species education modules will help you become more comfortable with identifying these terrestrial plant and aquatic plant species in the field. Each module (approximately 20 minutes) includes a short ten question quiz at the end to help you assess your newly acquired knowledge.

Identifying Aquatic Weeds
Mississippi State University Extension Service.
Includes information for how to submit a sample.

Help with Aquatic Plant Identification
New Hampshire Department of Environmental Services.

Plant Identification - AQUAPLANT
Texas A&M University. Department of Wildlife and Fisheries Sciences.
"AQUAPLANT is designed to help you identify aquatic plants using photos, drawings, and descriptions. Using this section involves viewing photos and drawings of aquatic plants until you identify the plant in question."

Virginia Tech Weed Identification Guide
Virginia Polytechnic Institute and State University. Plant Pathology, Physiology, and Weed Science.
Aides in the identification of common weeds and weed seedlings found throughout Virginia and the Southeastern U.S.

Aquatic Weed Identification Flow Chart (PDF | 234 KB)
King County (Washington).

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What Tree Is That? Tree Identification Field Guide
Arbor Day Foundation.

Identification Key to Weeds
University of California. Statewide Integrated Pest Management Program.

Weed Identification Tool
University of California. Cooperative Extension and Agricultural Experiment Station.

Colorado Noxious Weed Identification Key
Colorado State University. Adams County.
"Residents of Adams County are welcome to call, email, or bring a plant sample to the Extension office for identification."

Weed Identification Tool
Colorado Weed Management Association.

Leafsnap: An Electronic Field Guide
Columbia University; University of Maryland; Smithsonian Institution.
Tree identification mobile app using visual recognition software to help identify tree species from photographs on their leaves.

Field Guide To The Identification of Japanese Stiltgrass: With comparisons to other look-a-like species (Dec 2012)
University of Georgia. Center for Invasive Species and Ecosystem Health. Bugwood Blog.
Prepared by: Alabama Cooperative Extension System. ANR-1457.
This publication provides descriptions and clear pictures of key characteristics as well as details on how to distinguish several common look-a-like species.

Hawaii's Invasive Plant Species: A Noxious Weed Identification Key
Hawaii Biological Survey.

University of Illinois Plant Clinic
University of Illinois at Urbana-Champaign. Extension.
"Provides plant and insect identification, diagnosis of plant disease, insect, weed and chemical injury (chemical injury on field crops only)."

Weed Identification
University of Illinois at Urbana-Champaign. Illinois Council on Food and Agricultural Research.

Identifying Weeds in Field Crops
Michigan State University. Integrated Pest Management Program.

Weed ID Tool
Michigan State University. Department of Crop and Soil Sciences.

Training - Species Identification
Michigan State University. Midwest Invasive Species Information Network.
The invasive species education modules will help you become more comfortable with identifying these terrestrial plant and aquatic plant species in the field. Each module includes a short ten question quiz at the end to help you assess your newly acquired knowledge. Completing a module should only take about 20 minutes.

Plant Finder
Missouri Botanical Garden.
"The Kemper Garden Center at the Missouri Botanical Garden has pictures, plant information, and sources for many natives that are in the horticultural trade. You can search by scientific or common name. Through their PlantFinder Search options you can also search by preferred habitat, growth form, use (water plant, attracts butterflies, dried flowers, etc), and other characteristics, like good fall color."

Missouri Plants

"Provides photographs, descriptions, and keys to the flowering and non-flowering plants of Missouri. This site has a brief key you can click on based on flower color and leaf arrangement. You can scan through images to find the plant you are looking for. The individual plant pages have descriptions and details illustrated by beautiful close-up photos of plant parts like leaves and stems, often showing the range of variation that can be found in a single individual."

Mistaken Identity? Invasive Plants and their Native Look-alikes: an Identification Guide for the Mid-Atlantic (Nov 2008; PDF | 7 MB)
New York Botanical Garden.
Published by the Delaware Department of Agriculture in collaboration with Claude E. Phillips Herbarium at Delaware. State University and Delaware Center for Horticulture
"This publication is a full-color, 62-page booklet. The purpose of the work is to facilitate correct identification of confusingly similar invasive and native plant species. Targeted at land managers, gardeners, conservationists, and all others interested in plants, this booklet covers over 20 invasive species and their native look-alikes."

Exotic Thistle Identification Key
University of Nebraska - Kearney.

Turf & Weed Identification
North Carolina State University. Center for Turfgrass Environmental Research & Education.

Ask Mr. Smarty Plants
University of Texas at Austin. Lady Bird Johnson Wildflower Center.

Grass Weed Identification Guide
Virginia Polytechnic Institute and State University.

Virginia Tech Weed Identification Guide
Virginia Polytechnic Institute and State University. Plant Pathology, Physiology, and Weed Science.
Aides in the identification of common weeds and weed seedlings found throughout Virginia and the Southeastern U.S.

PLANTS Interactive ID Keys and The PLANTS Database
USDA. Natural Resources Conservation Service. National Plant Data Center.

Plant Identification Tools and Guides
USDA. Natural Resources Conservation Service.

Weed Identification Help
King County (Washington).

Weed Identification
Weed Science Society of America.

Weed Identification Tool
University of Wisconsin.
"The database contains 280 of the most common weeds/invasive plants found in agricultural, urban, and natural settings in Wisconsin. The database is organized to ask questions about the unknown plant, and, based on the user's input, the website will produce a list of plants (scientific and common names) along with thumbnail images that match the information entered."

Weed Identification and Management (DVD)
University of Wisconsin. Cooperative Extension.
This DVD (fee based) captures Jerry Doll's short course on weeds, complete with 28 lectures, live video of weed identification, plus video demonstrations of sprayer calibration, rotary hoeing and cultivation, and safe handling of pesticides. This resource will be beneficial to students and professionals alike. An excellent tool to supplement weed-related courses at any university, as well as for crop consultants and anyone else interested in weed identification and management.

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Arthropod Identification
American Museum of Natural History.

Amphibian and Reptile Identification
University of Florida. Department of Wildlife Ecology and Conservation.

Pest Alert: Giant African Land Snail And Giant South American Snails: Field Recognition
Florida Department of Agriculture and Consumer Services. Plant Industry.

Insect Advice from Extension (includes fact sheets and identification service information)
Pennsylvania State University. College of Agricultural Sciences. Entomology.

Wildlife Damage Inspection Decision Tree
Internet Center for Wildlife Damage Management.

Antkey - ID Guide for Introduced Ants
USDA. APHIS. PPQ. Identification Technology Program.
Antkey is a community resource for the identification of invasive, introduced and commonly intercepted ant species from across the globe. Developed through collaboration between USDA's Center for Plant Health Science and Technology (CPHST) and the University of Illinois, Antkey focuses on over 115 ant species that are introduced, invasive or commonly intercepted in the U.S. including Hawaii. Antkey seeks to mitigate the spread of established introduced ants and prevent the incursion of new introductions by providing quarantine personnel, inspectors and conservation biologists with a user-friendly identification tool specifically designed for non-specialists. Antkey is the second in a series of digital ant identification tools specifically designed and developed for non-specialists. The first tool, PIAkey: Pacific Invasive Ant Key was released in 2008.

PIAKey - Invasive Ants of the Pacific Islands
USDA. APHIS. PPQ. Identification Technology Program.
The Pacific Invasive Ant Key (PIAkey) is an illustrated identification guide designed to assist users identify the most common and dangerous invasive ant species threatening the ecosystems, economies and people of the Pacific Island region.

Bug Bytes
USDA. Agricultural Research Service.
Includes sound files of various insects (including invasive insects as well as links to pictures or other information about each species).

Light Brown Apple Moth Screening Aid

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Diagnosing Tree Disorders
Colorado State University. Extension.

Plant Disease Diagnostic Clinic
Cornell University.

Plant Disease Clinic
University of Minnesota. Department of Plant Pathology.

Common Tree Diseases of British Columbia
Natural Resources Canada. Pacific Forestry Centre.

Diagnostic Keys to Major Tree Fruit Diseases in the Mid-Atlantic Region
West Virginia University - Kearneysville.
"The diagnostic keys for deciduous tree fruit diseases (apple, peach, nectarine, and cherry) were developed to aid field personnel in the identification of diseases that are common to the mid-Atlantic region of the United States."

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Last Modified: Nov 26, 2014
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