The following sites can help you identify fall leaves:

  • Audubon Field Guides Register for free access to all the field guides.   Then select the tree icon.  The Guide to North American Trees is completely interactive with over 800 species of trees found in North America north of Mexico, covering species of the continental United States and Canada.
  • Audubon Trees App Carry your field guide on your iPhone, iPad or iPod Touch with an inexpensive mobile app from the Audubon Society.  Identify your tree and share it with your friends using Audubon’s Nature Share feature.
  • Common Trees of Pennsylvania Sponsored by the PA Department of Conservation and Natural Resources, this site is organized according to leaf shape and arrangement. Choose from the list of names of 57 native trees and 5 trees introduced to PA to identify your leaf.
  • Guide to Common Trees of Pennsylvania Match your leaf to the botanical drawings on Cook Forest Online.
  • Identifying PA Trees Learn to identify leaves and parts of trees with this tutorial developed by Penn State Natural Resources Extension.
  • Planning a “Leaf Peeping” outing?   Check the weekly fall foliage map and report from the PA Department of Conservation and Natural Resources and learn why autumn leaves change colors.
  • Take a Walk in the Forest and identify several trees by their leaves in an interactive game from the National Zoo.
  • Virginia Tech Tree ID Fact Sheets Search an extensive database with colorful photographs to learn more about your tree.
  • Virginia Tech Tree ID App Use this free mobile app for your Android Smart Phone, iPhone or iPad to link to fact sheets for almost 1,000 woody plants.  Narrow your search by entering your GPS coordinates.
  • Tree ID Guide Identify your leaf by shape in this guide from the University of Tennessee.
  • Forest Academy Learn fun facts and play games about trees and forest ecology from the Domtar Corporation, a Canadian manufacturer of wood-based products.
  • Leaf Tree ID Key Identify your leaf through a series of pictures provided by the Wisconsin Center for Environmental Education or find out more about your leaf by searching a tree name.
  • Leaf Invaders See if you can correctly identify each leaf before it hits the ground in an interactive game from the Missouri Conservation Commission.
  • Temperate Deciduous Forest This mini-guide sponsored by the Missouri Botanical Gardens will help you identify particular trees by the shape of their leaves. Find out more facts about the temperate deciduous forest by going to the site’s home page.
  • Tree Identification Key Answer a series of questions or look carefully at color photographs of leaves to identify your leaf on this site from the Michigan State University Extension.
  • What Tree Is It? Designed by the Ohio Public Library and Information Network, this site enables you to identify a tree by the name of a tree, the type of fruit it bears, or its leaf.
  • What Tree is That? Select a leaf type, then answer questions to discover its identity with this interactive game from the Arbor Day Foundation. View all the trees and use the tree identifier on the online edition of What Tree is That
  • A site sponsored by Garden Buildings Direct includes quite a few links that can help with tree identification: What Tree Is It?
  • Still puzzled about your leaf?  Try Leafsnap.   Snap a picture with your iPhone or iPad and learn about your tree with this free mobile app developed by the Smithsonian Institute, Columbia University and the University of Maryland.