This new study was created for landscape professionals by a committee of landscape professionals from four disciplines: landscape architects (CCASLA), nursery and greenhouse growers (CNGA), municipal arborists (via the Colorado Tree Coalition), and horticulturalists (CSU Extension). The study creates a working list of readily available trees "...with the ultimate goal of a healthy, diverse, and geographically appropriate landscape and urban forest." The study focused on Colorado's Front Range, from Colorado Springs north to the Wyoming border and from the foothills to the eastern plains.
Nearly 300 trees were evaluated and rated as:
A - Generally recommended
B - Conditionally recommended
C - Potential/Unproven
D - Not recommended
Thirteen different cultural factors that could affect the ratings were listed as critical or cautionary. Water needs and availability were also noted.
So how did the trees in my own garden rate?
|Japanese Tree Lilac, Syringa reticulata - A|
|Red Oak, Quercus rubra - B (develops chlorosis in alkaline soils)|
|Autumn Brilliance serviceberry, Amelanchier x grandiflora - B (basal suckering;use as shrub)|
|Apricot, Prunus armeniaca - A (rarely sets fruit)|
|Autumn Purple ash, Fraxinus americana - B (susceptible to sun scald)|
|Common hackberry, Celtis occidentalis - A (re-seeds)|
Although the list is not exhaustive - for example, I was surprised to see that no ornamental plums were included - it's a great starting point and is meant to be a work in progress. If you are interested in viewing and downloading a copy of the Front Range Tree Recommendation List©, click here.