We need more trees in Downtown Denver. To explain, I’m going to quote myself from a blog I did in September 2007 about Portland, Oregon’s Downtown treescape:

“Trees. They are such a critical element in a downtown streetscape, given all the concrete, asphalt, brick, and other hard and heat-radiating surfaces found in urban centers. In Denver, our Downtown treescape is in poor shape. The trees along 16th Street are generally in good condition and have grown over the past 25 years to create a relatively nice canopy along the Mall. But venture down just about any other Downtown Denver street, and you’ll find plenty of frail specimens looking all battered and abused, jagged stumps poking up from the sidewalk like broken-off toothpicks, and empty tree grates harboring weeds. Given the ubiquitous sunshine in Denver and our increasingly scorching summers, we need all the Downtown trees we can get.”

We also need to take better care of our Downtown trees. It’s very discouraging to see trees that are dead or severely stressed, but still sitting in their tree grate on the sidewalk. That would be like leaving the carcass of a dead animal on the sidewalk until its body decomposes. We would never allow that, yet we allow dead or dying trees to remain in place for years. Except for the trees on the 16th Street Mall and in parks and a few other places, the maintenance of Downtown trees are the responsibility of the owner in front of whose property the tree sits. So the next time you’re Downtown and you spot a dead tree or an empty tree grate, look at the building you’re standing in front of, and you’ll know who to blame.

How many trees are there Downtown and how do we know it’s not enough, you might ask? John D. at the Downtown Denver Partnership did a partial tree survey this past summer, and he was kind enough to share the data with me. The survey focused on just the named streets, from Cleveland Place to Larimer Street, and the blocks between 14th and 18th Streets (the 1400, 1500, 1600, and 1700 blocks). Also, two assumptions: 8 is the desired minimum number of trees per block face (or 16 trees per block), and the named streets run north-south. Using his raw data, I’ve created the following table:

What does this information tell us? Here are some key conclusions:

  • Based on the minimum standard of 8 trees per block face, the survey area in total has only about 56% of the street trees that it should have.

  • Collectively, the 1700 blocks are the best off, with about 73% of the trees they should have, followed by the 1500 blocks with 58%, the 1400 blocks with 50%, and the 1600 blocks with only 43%.

  • Curtis Street is the best off, with about 84% of the trees it should have, followed by California (76%), Larimer (72%), Arapahoe (62%), Stout (58%), Lawrence (55%) and Cleveland (50%). Having less than half the desired number of trees is Welton (44%), Tremont (41%), Court (39%), Champa (36%), and finally Glenarm, with only 30% of the minimum number of street trees.

  • Of the 88 total block faces in the study group, 27 of them (31%) were at or greater than the desired minimum. Of the remaining 61 block faces with some kind of shortfall (anywhere from 1 to 8 trees) about one-third (22) had a shortfall of 1 to 4 trees, and about two-thirds (39) had a shortfall of 5 to 8 trees.

  • A total of 26 block faces (30% of the entire survey group) don’t have a single street tree!

Keep in mind that this survey did not take into consideration the quality (i.e. health) of a tree, only if a tree was present. In fact, a few of the trees counted were noted as being dead, but were counted nevertheless.

Planting more trees is one goal, keeping every tree in a vibrant state of health is another. Our current system of relying on property owners to maintain the street trees in front of their property is obviously not working very well. We need to either vigorously enforce the current requirements, or make the maintenance of all trees in the Central Business District the responsibility of some entity that can ensure the trees are irrigated, pruned, and cared for on a regular basis. One way or another, we need a Downtown treescape that provides ample shade, shelter, and aesthetics for the pedestrian.