Rotate Your Stock: Considering What Trees to Plant

Before automation, this message was a familiar sight in hardware and grocery stores where goods had a shelf life.  The idea was the older items should be moved to the front of the shelf for quicker sale. In today’s retail stores, older or seasonal goods are displayed with clearance signs enticing us to buy, making room for newer merchandise. 

The same concept applies in nature. In the mountains, after a significant event (fire, pestilence, logging, mining), aspen trees are first to inhabit the site.  As aspen age, the stand naturally thins itself allowing pine and spruce to sprout.  If you ski, this is a phenomenon you can see while riding the lifts and gondolas.

In our landscape, when a tree declines or dies, nature does not take care of its replacement. It is up to us to plant it. There is a bit of strategy to all of this. 

Consider aspen trees. Young aspen grow quickly providing a nice display in the landscape. Old aspen lose their lower branches, drop leaves early in the season, and are beset by a plethora of pests. In Colorado Front Range landscapes, aspen have a useful life of plus or minus 20 years. Aspen owners should thin or remove older stems (trunks) to allow new sprouts to emerge, or plant small aspen in the open space.

Trees such as cottonwood and silver maple are fast growing and soft wooded. These trees are prone to breakage and many were damaged in last fall’s snow storms. While you may not be ready to part with the damaged trees, consider planting something additional in the landscape to be ready when the time comes. 

Four million ash trees call Colorado home  Now many city foresters and experts are casting a wary eye on ash.  Emerald ash borer is responsible for killing tens of millions of ash in the mid-west and eastern United States. (For more information visit the US Department of Agriculture's Animal and Plant Health Inspection Service.) This pest has not been detected in Colorado and there are insecticide controls for this borer.  Still, it is a good idea to limit the number of ash and have other trees planted in the landscape. 

Now is the time to venture outdoors and strategize. Identify plants that are not thriving and where you could plant to increase the appeal of your property. Not every tree or shrub displayed in the nursery or store will thrive in your individual landscape. Mature size of the tree or shrub and specific growing conditions dictate success.  Your tree care professional, garden center and municipal forestry office are good sources for advice. 

For a comprehensive Colorado list of trees visit Colorado State University's Front Range Tree Recommendation List.