Two fairly common trees that are easily identifiable by their leaf shapes is the Sweet Gum, Liquidambar Styraciflua, and the Sycamore, Platanus occidentalis. The Sycamore trees are found almost everywhere in the deciduous forest areas of the United States. Many times, you'll find them in cities and parks and other times near the shores of small ponds and lakes. The The Sweet Gum gets it's name from the nice smell of its leaves. These leaves have 5 main lobes and is star shaped.

The last four leaves that we're going to look at are from four oak trees from around the country. The Post Oak, Quercus Robur, is a small leaf that ranges from 2" to 4" and has ear-like lobes at the base. I has a very, very short stem. These trees got their name because the colonies that settled in America during the 17th and 18th centuries brought them over from England. The Post Oak, Quercus stellata, is the lower left leaf in the picture. If you notice, the three end lobes of the leaf are much larger than the others. These trees are found on the edges of forests in the south and southeastern parts of the United States. It tolerates moderat shading and you will usually find the trees in rocky and gravel-like ground. The Post Oak, Quercus alba, is also another tree found throughout the deciduous forests of the United States. An interesting characteristic of the Bur Oak, Quercus macrocarpa, is that the leaf is cut nearly to the midrib in the middle of the leaf. The upper-half of this leaf is not as deeply lobed as the bottom half which can be seen in the illustration.

If you want to learn more on how you can identify trees throughout the North American continent by the shapes of their leaves, read Tree Finder, A Manual for the Identification of Trees by Their Leaves written by May Theilagaard Watts. It's a mini guide to over a hundred trees and their types of leaves.