By DAVE SHILEY
Winterlike weather has probably kept most people from thinking about planting trees and shrubs in their yards, but warmer weather will get us thinking about those planting projects.
Although trees and shrubs can be successfully planted in the fall, spring is the best season to plant seedling sized trees or shrubs. The summer growing season allows a strong root system to develop, which equates to survival.
However, other types of nursery tree and shrub planting stock, such as container-grown or balled and burlap, also benefit from spring planting.
Before you purchase your trees or shrubs for spring planting, there are a few things to consider.
First, consider the function of the tree or shrub in your landscape. Will it be used for shade, screening of noise or wind, fall color or wildlife benefits? Do you have adequate space for another tree or shrub in your landscape? For example, most shade tree species, such as maple, ash and oak, require a spacing of 16 to 20 feet between trees.
If you are planting a windbreak with pine and spruce species, the trees should be spaced 16 feet apart to function properly in the long run. These two groups of evergreens are shade-intolerant, which means that the lower branches can die back if trees are crowded and shaded.
When these lower branches die back, a hole is created in the windbreak, causing a wind tunnel effect at the ground level. If this occurs, a corrective planting would be necessary.
Remember, too, that unless a tree's mature height is less than 15 feet, it should not be planted under or near overhead utility lines. You might want to consider planting shrubs in these areas.
Finally, determine whether the tree or shrub you want to plant is hardy for your climate, and is adapted to your soil type. A tree or shrub that is native to your region of Illinois will usually be easier to establish and maintain, and is often more resistant to disease and environmental stress.
The University of Illinois Extension has two websites that can help you select a tree or shrub that is appropriate for your landscape.
The "Selecting Trees for Your Home" website can be found at http://www.urbanext.uiuc.edu/ treeselector/, and if you are planning to add shrubs to your landscape, go to the "Selecting Shrubs for Your Home" website at http://urbanext.illinois.edu/ ShrubSelector/.
Give your new tree or shrub a good start by planting it correctly. If you are planting trees or shrubs that have been grown in a container or have a root ball covered with burlap, there are two important planting steps.
First, the width of the hole you prepare should be two to three times the diameter of the root ball or container. Secondly, the plant must not be planted deeper than it was originally growing in the nursery.
When you are ready to plant, carefully remove the container and the soil at the top of the container or root ball, and look for the root collar. This will be a slightly swollen area where the stem of the tree meets the roots; then plant it no deeper than this point.
If you are planting bare rooted seedling trees or shrubs, look for the root collar and do not plant it deeper than this point. If you are planting seedlings with a spade or planting bar, make sure the slit is deep enough so the root tips are not bent upwards when placed in the slit, as this often leads to the death of the tree or shrub seedling.
Finally, water the tree to the point of soil saturation at the time of planting. Then during the growing season, make sure that your tree has 1 inch of water weekly from rainfall or artificial watering. Mulching will help reduce evaporation and will also keep the roots cooler and less stressed in late summer.
If you have questions about tree or shrub selection or planting, the UI Extension office in Champaign can be reached at 333-7672, or I can be reached at 543-3755.
Dave Shiley is educator for local food systems and small farms for the University of Illinois Extension. You can reach him at 543-3755.