Most trees in our landscapes today are not native to the Salt Lake valley. Before the valley was settled, mainly just the Cottonwood tree was present, and usually only along streams. Looking to our nearby mountains doesn’t always provide the right answer for our home landscapes. Natives such as Alder should be planted near a stream; Aspen and Rocky Mountain Maple prefer cooler, moist conditions and struggle in our hot and dry valley landscapes. However, there are many native and non-native trees that perform well in Utah, and with a few tips, you can select one that is suitable for your site.
Location/exposure – consider things like sun and shade, windy corridors, utility lines, etc. Trees planted on the south or west face, or locations with reflected heat from buildings or hardscape, must tolerate hotter and drier conditions than trees planted on a north or east face. Trees in Utah must tolerate temperature extremes, not only hot dry summers, including hot dry winds, but also cold winters. Is there enough space for the tree to reach maturity? Consider not only above ground space, but also the soil volume needed to sustain a healthy mature tree. Trees planted under a powerline should only reach 16’ feet tall at maturity, and near a powerline but not under, should only reach 25’.
Soil – is your soil sandy or clay? What is the pH and salt content of the soil? Some trees such as Red Maple, Ginnala Maple and Pin Oak perform poorly in high pH soils, which are so predominant in Utah. Some trees tolerate salty conditions, some tolerate wet conditions, and many others require well-drained soils. If you don’t know your soil conditions, you can request a simple soil test kit through the local Extension Service; in Salt Lake, it is located on 21st South and State St.
Water – will the tree receive irrigation? What type of system and how much? Be sure to select a tree whose water requirements are similar to the plantings in the surrounding landscape. Tree roots spread much wider than previously thought, so it’s very important to plan the landscape as a whole, or match the trees water requirements to that of the existing landscape.
Consider the characteristics of the tree itself. Do you want shade or flowers? Other options can include colorful or exfoliating bark, persistent fruit, evergreen foliage, or various habits, such as weeping or columnar forms. Some characteristics, such as thorns or fruit, may be undesirable in certain situations. Be sure the tree you choose is resistant to known insects and diseases in your area, and be aware that large plantings of a single species can encourage the spread of insects and diseases.
Research the tree to determine if there are known negative characteristics. Russian Olive for example, once recommended, is now negatively affecting Utah’s natural habitats by preventing native plants, as well as fauna, access to streamsides. Native habitat restoration activities in Utah and Colorado have included the removal of Russian Olives. Shallow rooted trees such as Birch typically don’t perform well unless planted near water; the hot dry soil conditions in the typical home landscape leave these trees permanently stressed and predisposed to insects and diseases.
There are many, many good trees for Utah. The right selection for you depends on the careful consideration of all the above as well as your own personal preferences.