At Amazon.com In the USA:

• The National Audubon Society Field Guide to North American Trees: Eastern Region
• National Audubon Society Field Guide to North American Trees: Western Region
• Trees: Trees Identified by Leaf, Bark & Seed (Fandex Family Field Guides)
• First Guide to Trees (Peterson Field Guides)
• A Natural History of Trees of Eastern and Central North America
• Trees of North America and Europe/a Photographic Guide to More Than 500 Trees

At Amazon.com In the UK:

• Collins Wildlife Trust Guide: Trees of Britain and Europe
• Collins Pocket Guide: Trees of Britain and Northern Europe
• Trees of North America and Europe/a Photographic Guide to More Than 500 Trees
• Collins How to Identify Trees
• Collins Field Guide: Trees of Britain and Northern Europe
• Trees of Great Britain and Ireland