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A dichotomous key is a tool that allows the user to determine the identity of items in the natural world, such as trees, wildflowers, mammals, reptiles, rocks, and fish. Keys consist of a series of choices that lead the user to the correct name of a given item. "Dichotomous" means "divided into two parts". Therefore, dichotomous keys always give two choices in each step.

Directions for using the dichotomous key for tree identification:

  • A set of choices will appear on the screen, with the word "start" at the top. Choose one of the two items by clicking on one of the white boxes.
  • After a choice is made in the first step, a second set of choices will appear. The previous choice you made will appear at the top, where the word "start" was before. Keep clicking on the boxes that best describe the characteristics of the tree you are trying to identify.
  • Eventually your choices will lead you to the name of a tree genus. Clicking on the box with a genus name will connect you to a description of that particular genus. From the genus description page you will also be able to connect to a species page to view pictures of the native tree species contained in that genus.
  • If you are trying to determine the identity of a "mystery tree", work through the key until you reach the tree species that matches the given characteristics. Then, return to the mystery tree page to find the solution to your mystery tree. If your tree doesn't match the solution, go back through the key again to try to reach the correct tree.

Are you ready to identify your tree?

Click here to connect to the dichotomous key!



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