Everyone says they love trees. Practically every one of the millions of trees in the Front Range was planted by someone. Dutch Elm disease removed most American elms fifty years ago, and Thousand Cankers is busy wiping out the Black Walnuts right now. And Emerald Ash Borer is not likely to be contained in Boulder County much longer. If, and when, the insect appears in Denver Metro, it is possible that a million trees could die in a few years: the cost for removing these is likely to cost over a billion dollars in Colorado alone.
The other costs: the loss of cooling by trees (these are the lungs of the city, and the air conditioners) will result in greater fuel costs for air conditioning. And the greatest loss is that of beauty. Trees are the living sculptures that line our lives as much as they line streets. The study of Biophilia has shown that trees and nature have an enormous impact on psychological well-being. The loss of either is a subtle blow to our psyches.
If Ash trees, a major component of our street tree palette, do disappear will we just replace them with a new monoculture? More and more nurseries are selling trees propagated asexually, greatly diminishing the genetic diversity of our Urban Tree Flora. Compare the leaves on these Burr Oaks selected from a row at Chatfield Farms grown from the same seed lot—this is genetic diversity in action!
Why does diversity matter? Not only does a wider palette of trees provide a richer paint box with which to color the canvas of our cities—diversity provides buffers for potential pests and diseases. Monocultures are far more prone to rapid spread of both of these threats. Be sure to attend the tree conference to learn more.
2017 4th Annual Tree Diversity Conference
Friday, March 10
8:30 a.m. – 4 p.m., York Street
Registration includes lunch
This Tree Diversity Conference brings five of the leading authorities on Street Trees to Denver.
- The Director of America’s National Arboretum in Washington, whose focus professionally has been on Street Trees.
- A nurseryman from Oregon who’s explored the world for plants, and who has a home in the desert which rarely gets more than 10” rainfall.
- A nurseryman from Littleton, CO who went on to convene the biggest short course on trees in the hemisphere.
- The director of a statewide network of Arboreta in our neighboring state, unique in the world for its outreach to their community.
- And the Top Gun Arborist of Denver who’s led the charge to identify and monitor every street tree in Denver City and County.
These seasoned Arborists will be as enthralling and entertaining as they are knowledgeable. Be there (or stick to astroturf)!