The Tree Register of the British Isles
- Historical, ancient, and biggest trees of Great Britain and Ireland.
- http://www.treeregister.org/

Trees, Shrubs, and Woody Vines of North Carolina
- Photographs and information on over 330 species, identification key, and full species list for the state.
- http://www.duke.edu/~cwcook/trees/

Tree Atlas of the Panama Canal Watershed
- Species accounts with images and maps, arranged by scientific name, tanomomy, and common name. In English and Spanish.
- http://ctfs.si.edu/webatlas/maintreeatlas.html

Conifers in the Pacific Northwest
- A site that covers common conifers only. Uses an interactive web based dichotomous key.
- http://oregonstate.edu/trees/

Goo's Tree Encyclopedia
- Names and illustrations of Japanese trees.
- http://www005.upp.so-net.ne.jp/goostake/GOO/XSCNAMEK.HTM

Forest Trees of Florida
- Descriptions and images of over 70 species.
- http://www.sfrc.ufl.edu/4h/Trees_Plants/Trees/trees.html

Ariadne's Trees and Forests
- Glossary of tree-related terms; articles on California trees, hiking, and meditation.
- http://www.icogitate.com/~tree/

Identifying Trees of Michigan
- A page on the common trees of Michigan with a key.
- http://www.msue.msu.edu/msue/imp/modft/23320001.html

Identification of Common Trees of Iowa
- An interactive guide to trees, using a simple visual dichotomous key.
- http://www.exnet.iastate.edu/pages/tree/

Common Trees of Pennsylvania
- Guide to common trees with laymans descriptions of each tree, and a simple key to start with. Line drawings of leaves and fruit.
- http://www.dcnr.state.pa.us/forestry/commontr/common.htm

Catalog of the Woody Plants of Oklahoma
- Descriptions, images, and range maps.
- http://www.biosurvey.ou.edu/shrub/shrubndx.htm

Trees of Alabama and the Southeast
- Brief text and numerous photos of both native and planted trees. Includes section illustrating terminology with photographs.
- http://www.forestry.auburn.edu/samuelson/dendrology/

About.com: Top 100 Trees
- Find information on more than 100 trees in North America
- http://forestry.about.com/library/tree/bltredex.htm

British Trees
- Guide to the native trees of Britain, plus links to other web resources on forestry and conservation of British Native trees, including forest conservation organizations.
- http://www.british-trees.com

Trees and Shrubs of Ontario
- Designed to assist those interested in learning some of the common trees and shrubs found in the province.
- http://gaia.flemingc.on.ca/~dhendry/welcome.htm