Trees in both urban and rural forests have been changing from green to yellow, orange and red for several weeks. Autumn is a favorite season for many Illinois residents because of this display of brilliant colors.

The fall display of colors by trees may make you wish you had a particular tree in your landscape. The fall is a good time to plant potted or balled and burlap trees, and a good time to save a little money at your local nursery.

Tree species differ in their ability to produce a variety of colors. Yellow leaf color is typical in tree species such as birch, elm, hackberry, hickory, sycamore and willow. The yellow is intensified to gold in species such as ash, buckeye and yellow poplar. If you want to add red to your landscape you may want to select a red or sugar maple or Illinois' state tree, the white oak.

The tree's fall color is only one of several considerations you must take into account when selecting a tree. Do you need a tree for shade, screening of noise or wind, or wildlife food? The amount of space you have for a tree is another very important consideration. For example, most shade tree species, such as maple, ash and oak require a spacing of 16 to 20 feet between trees. Pine and spruce planted as a windbreak require 14 to16 foot spacing in most situations.

Don't forget about upward space as well. If a tree's mature height is more than 15 feet, it should not be planted under or near overhead utility lines. A tree's roots need space too. Plant large shade trees at least 16 feet away from foundations, driveways and patios. Most of a tree's roots are in located in the upper 18 to 24 inches of soil, but old clay tile sewer lines may also become clogged with roots, if you plant a tree too close to a sewer line's location.

Before you buy a new tree for your landscape, make a simple map of your property, showing existing utilities, buildings, trees and activity areas. This will help you determine the amount of space you have available for new trees.

Another important step in tree selection is the species' hardiness to our climate. Trees that you will find available at the local nursery are hardy for central Illinois. However, if you purchase a tree in another state through a mail order or website catalog it may not fit our plant hardiness zone.

When you have finished planning and selecting an appropriate tree, then it's time to plant. Proper planting techniques can be critical to your tree's survival. The tree must not be planted deeper than it was originally growing in the nursery. Plant the tree to a depth that will put the top of the root crown at or very near the ground's surface. The root crown is where the main roots of the tree spread out from the trunk, usually this is the top of the container or root ball, but gently dig around the base of the tree to make sure additional soil wasn't added to the top.

The width of the hole you prepare for your tree should be 2 to 3 times the diameter of the root ball or container. This will allow the roots free growing space to rapidly expand during the next growing season.

Finally, water the tree to the point of soil saturation at the time of planting and then insure that your tree has one inch of water weekly until the ground freezes this fall and throughout the growing season for at least two seasons.