A basic knowledge of the common leaf shapes can help with tree and plant identification.  Here are the common leaf shapes you may encounter in the Rocky Mountains.

If you do a google search or look at different books you are sure to find a lot of different leaf shapes.  Some sources list more and others less, which can be confusing.  I want to keep things simple and so am listing only the most common leaf shapes here.  Combining this with knowledge of common leaf arrangement, and leaf edges should greatly aid in plant and tree identification.

Leaf Shapes Or Leaf Arrangements?

These two terms sound similar, but refer to different things.  The leaf shape refers to the overall shape of the leaf when you look at it.  As the below examples show there are many different kinds of shapes.  Be careful though as some trees or plants may have more than one leaf shape.

In contrast to this, leaf arrangement refers to the way that the leaves come off of the stem of the plant. There are far more different leaf shapes than there are leaf arrangements.

Common Leaf Shapes

Oblong (a long leaf)

Lanceolate or Lance Shaped

Oblanceolate (this is the reverse of lanceolate)

Ovate (thick at the ends and wide in middle)

Rounded or Orbicular

Heart Shaped

Elliptical (similar to ovate, but narrower at the ends)

Arrowhead or Spear Shaped

Lobed

Examples of Leaf Descriptions Of Trees

When describing the leaves on a tree you will need to note the leaf form, leaf shape, leaf edge, and leaf arrangement.

Quaking Aspen – simple, heart shaped to rounded leaves, fine toothed, and alternate.  This mean that this leaves of this tree are just one (simple), shaped round or like a heart, have tiny teeth on the edges (fine toothed), and come off the stem in an alternate pattern.

Box Elder – pinnately compound, toothed, shallow lobes, and opposite.  This means that these leaves are made up of a central stem with many smaller leaves coming off of it (pinnately compound), have sharp edges (toothed), and come in slightly on the sides (shallow lobes), and come off the stem opposite of other leaves such that two leave come off the tree on opposite sides at the same time.

For More Information On Plant and Tree Identification Using Leaves

For more information on using leaves to help with plant and tree identification check out:

Common leaf arrangements for beginners

Common leaf edges for beginners

Common plant and tree terms for beginners

I am going to make one final post on leaves to help with identification.  It will talk about the common leaf forms.