The Benefits of Trees – Plant One Today!

Arbor Day is April 24, and many of you may be considering adding a tree, or maybe several trees or shrubs, to your landscape.

Before we get to the important steps of tree selection and planting, let’s take a moment to recognize some of the benefits of trees. Try to imagine your home landscape without any trees or shrubs. Are you happy with that image? I think most of us would agree that trees and shrubs add aesthetic and real value to our landscapes.

Trees provide benefits by helping to clean our air, absorbing carbon dioxide and providing oxygen through photosynthesis, helping clean our water by reducing runoff, providing wildlife benefits, increasing property values, contributing to good health by reducing stress, and shading our homes and providing some protection from winter winds, both of which can save energy costs.

Functionally, trees in our landscapes can provide shade, offer screening (natural fences/privacy), provide prominent focal points (specimen trees), prevent erosion, provide windbreaks in rural areas, and provide food, shelter, and homes for wildlife. If you can add multiple native trees, it will multiply wildlife benefits.

You might think of other benefits or valuable functions of trees and shrubs in your landscape.

Before planting, evaluate the purpose of the tree(s) and select the proper tree for the intended site(s). This involves a little research.

Purdue specialists have authored a Purdue Extension publication, “Tree Selection for the ‘Un-natural’ Environment,” which describes the built environment of home landscapes and urban settings.

“Successful tree selection requires us to think backwards – beginning with the end in mind – to get the right tree in the right place…in the right way,” they said.

First, they encouraged homeowners to determine why they are planting a tree. This includes the tree's intended function in the landscape, its ornamental value, and the suitability of the species for the area.

Beyond the functions discussed above, trees offer many ornamental qualities. Consider leaf color, texture, and flowers and fruit during the selection process. “Some species provide beautiful displays of color for short periods in the spring or fall,” they said. “Other species have foliage color displays that add interest year-round.” If you want green foliage year-round in some parts of your landscape, that can be achieved with evergreens. Maybe you desire trees or shrubs that bear fruit or nuts, which offer color features along with the benefits they bring to wildlife.

To evaluate the suitability of a species for the location, consider soil moisture and drainage, topography, sunlight or shade, size, and tree shape. For example, certain trees or shrubs may struggle in wet areas, while others will thrive. Avoid using trees or shrubs that escape our landscapes and become invasive in natural areas.

After conducting research and selecting the right tree for the intended place in your landscape, it’s time to plant the tree correctly.

I recommend following the instructions in Purdue Extension publication FNR-433-W, "Tree Installation: Process and Practices."

Avoid the more common mistakes people make in planting trees.

First, people do not account for how large and how wide the tree will eventually be, so take care when placing the tree to account for its mature size.

Second, some people dig too deep a hole. The root flare (a.k.a. trunk flare) is a widening of the trunk where it transitions to the topmost root. It resembles the flaring of the bottom of a bell. This flared area should be visible above the finished soil grade of the planted tree. If planted too deeply, it will instead look like a telephone pole in the ground.

Third, many people over-mulch their trees by piling a “mulch volcano” around the tree. This is harmful to the tree in several ways. Instead, add 2-3 inches of mulch over the root area, and have no mulch at the trunk. In fact, it’s best to maintain a 2–3-inch air gap with no mulch touching the trunk.

Both referenced publications are available free of charge at Purdue Extension’s Education Store.