Discover: What Can I Learn from a Leaf?

Studying the shapes of leaves can help us identify trees.

In the following activities, you will learn that leaves have several more features than the pretty green colour.  By applying some simple rules and thinking like a detective, you can identify a tree.

  Video

Get some tips for identifying Alberta trees by watching the video:

ADLC - Digital Lesson on Alberta Trees

Watch this video again as you try to identify your samples in this activity!

Leaves can be identified by

  • the leaf arrangement on the stem
  • the structure of the leaf
  • the appearance of the leaf edge (or margin)
  • the shape of the leaf
Notes: You will need to know these terms and categories for the government PAT test.
Some leaves have stems or petioles that attach them to the branch.
 

Other leaves do not have a stem or stalk.  They attach directly to the branch.  These leaves are called sessile leaves.


Simple leaves are undivided blades. They do not have lobes, sections or individual leaflets.
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Lobed leaves have divisions that do not go all the way to the centre of the leaf.

Compound leaves are divided into various leaflets.
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Entire or Smooth - Some leaves have smooth edges.
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Serrated - Some leaves have jagged edges.  They have bent teeth like a saw.
 
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Crenate - Some leaves have rounded or scalloped edges
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Linear leaves are long and thin.

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Cordate leaves are heart shaped.
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Ovate leaves are egg shaped. They are wider at the base than at the top of the leaf.
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  Notebook: Can an Albertan tree be identified, using only a small sample of branch and leaf?

  1. Click here to download this activity. 
  2. Complete the activity using the links provided (in the activity and below).
  3. Save to your Trees Notebook.

Activity Links:


Challenge!

You can test your ability to use keys by extending your sampling to include shrubs as well as trees.  Repeat step 3 above, but include shrubs in your samples.  Use the Guide to the Common Native Trees and Shrubs of Alberta to assist you in your identifications.


  Literacy Connection

What is cultivation?

Not all trees in Alberta grow in the wild.  That's because some people take special interest preparing soil, planting seeds, and tending to plants.  This special attention is known as cultivation (kuhl-tuh-vey-shuhn), and it is why you often see interesting trees such as elms and apple trees in Alberta backyards.