By Shannon Moreau
Long lived and beloved, it’s no surprise that the oak is the national tree of the United States. There are a plethora of native species that grow from coast to coast bringing reliable, sturdy branches and dense shade. Beyond the canopy, there is also the added bonus of acorns! While oaks don’t usually come to mind first when thinking of shade trees in Colorado, there are several species that thrive here and they come in all shapes and sizes!
First, I’d like to clear up a misunderstanding about oaks. They are often lumped into the category of slow growers, which is a common characteristic for many hardwood trees. However, there’s more to it, and it’s no guarantee that every species of oak grows slowly! If planted in a good location with adequate light and water, a moderate growth rate can be expected from several species. Between species the growth rates can vary just as much as their leaf shape, acorn size, and fall color. There are still a few that will be slower, but I tend to think of this not as a negative, but instead as a long term investment in your landscape. Oaks are known for their hard wood, meaning they are less likely to lose branches and limbs due to heavy snow or wind, and they can be exceptionally long lived. Rather than reaching for trees that grow fast but can shed branches and/or are shorter lived, I urge you to look towards the oaks and plan for a beautiful canopy that can be enjoyed for many years.
Gambel Oak (Quercus gambelii)
- 20′ – 30’ tall x 20′ – 25’ wide
- Hardy to zone 4
Also frequently called “scrub oak”, this dense Colorado native performs well across the front range. Typically found growing native in dense masses, this species tends to hold its leaves through the winter, offering shelter and protection to birds, deer, and other wildlife. A few of my favorite stands can be found throughout Castle Rock and Colorado Springs, where they sprawl across the foothills. Outside of their native range they can be grown as a small multi stemmed tree or you can plant one of the newer single-stemmed forms like ‘Gila Monster’.
Shumard Oak (Quercus shumardii)
- 40′ – 60′ tall x 30′ – 40’ wide
- Hardy to zone 4
The large canopy of the Shumard oak makes it a wonderful shade tree. Although it is native to the Eastern United States it is adaptable to varying site conditions and soils. One of its best features is the brilliant wine-red fall color. Due to this brilliant red color they are often confused with the Red Oak (Quercus rubra), which are not planted as widely in Colorado because of their tendency to develop iron chlorosis, a problem that Shrumard oaks do not commonly experience.
Bur Oak (Quercus macrocarpa)
- 60′ – 80’ tall x 60′ – 80′ wide
- Hardy to zone 3
A classic in Fort Collins, these mighty majestic oaks are commonly planted as shade trees in parks and along roads. Bur Oaks are exceptionally hardy and sport a soft golden-yellow color during the fall. This is a selection that will grow vigorously when planted in the right site! If you are wanting a twist on the classic, selections like ‘Cobblestone’ produce extremely furrowed bark, leading to its clever name.
Columnar oaks (Crimson Spire and Regal Prince) Quercus spp.
- 35’ – 45’ tall x 8′ – 12’ wide
- Hardy to zone 4
It has been a delight to see these hardy selections rise in popularity. They are lovely choices for narrow locations and bring an air of formality into the landscape. Outside of the residential landscape I’ve seen many planted in parking lots and medians, demonstrating their resilience and hardiness in tough conditions with ample radiant heat. Crimson Spire lives up to its name, displaying fiery red fall color. This variety will hold onto its dried brown leaves long into winter, providing a visual barrier during the late fall and winter. While Regal Prince does not hold its leaves past autumn, the warm golden tone of its fall color and narrow habit still make it a great candidate for tight locations.
We are lucky to have a great Forestry department in Fort Collins that is trying new and exciting species of trees, including many varieties of oak. Take a look at their Recommended Plant List for other noteworthy species. To see this list of oaks and other hardy selections in person I highly recommend stopping by the nursery and visiting the following locations! They each demonstrate the versatility of these oaks.
– Denver Botanic Gardens
– Old Town Square in Fort Collins
– Front Range Shopping area (specifically the Super Target Parking lot) in Fort Collins
– Sierra Trading Post and Trader Joes Parking lot in Fort Collins.
– The CSU Trial Gardens (for two very large and mature Bur oaks)
Originally published on September 29th, 2025.