Lexington, KY - I’ve heard that it’s not a good idea to start an article on a down note, but I’m going to risk it. Keep reading, though –– it will get a whole lot better. First, the bad news. Lexington’s urban forest, which includes all of our trees, both on public and private property, is in trouble. Our canopy cover is about half what it should be and many of our existing trees are in poor health due to damage from insects and disease, improper species selection for the site, and poor planting and maintenance.
And more bad news. Of our approximately 50,000 street trees, fully one quarter are pear trees, which are now prohibited as street trees because of their poor structure and extremely invasive nature. Another 10 percent are ash trees, many of which will be lost to the emerald ash borer. You just can’t say that things are looking good.
Why should you care about the decline of our urban forest? Besides being beautiful –– a big plus –– what else do trees do for us?
Here’s some of that good news I promised:
Environmentally, trees are worth celebrating. Tree canopy and root systems slow and filter rainwater, reducing the impact of storms on our already beleaguered stormwater management systems. Trees remove many pollutants from the air and produce oxygen. And they have a marked cooling effect: as few as three trees properly positioned can save the average household between $100 and $250 annually in air conditioning costs.
There are also many social and economic benefits that trees provide.
Thing is, we don’t have enough trees for them to really work their environmental magic. The solution is obvious. We need to plant more trees. Not the government, not somebody else –– it’s up to each one of us to do our part. Trees are a community resource and we are the community.
To further encourage you to plant a tree or two, here’s more good news. Trees add value to your property. Thus, a tree is an investment. As with any investment, it is prudent to do your research and choose wisely.
Tree Selection
Some of the best investment advice you’ll ever hear is “right tree, right place.” Are there overhead utility lines that will limit the height available? How large is the planting area? Is the soil compacted? Is the site shady or sunny, wet or dry? There will be some tree species that will thrive on your site –– and others that are not likely to do so well. Get some advice from a trained arborist or from your county extension agent.
There are more considerations when planting a street tree. You must get a permit (no charge) to plant or remove a street tree. And there is a list of approved street trees to help guide your selection. As always, the “right tree, right place” advice applies. Our city’s urban forester, Tim Queary, is an excellent resource for assistance; his office number is (859) 258-3404.
Once you decide upon the tree species that you’re going to plant, you need to find a specimen with healthy roots, bark and good structure. It can be worth hiring a properly trained landscaper or an arborist to find you a healthy tree.
Proper Planting & Mulching
Proper planting is also essential to the long term vitality of your tree. Many trees are now container grown. These are lighter and easier for the homeowner to handle than “balled and burlapped” trees because they are planted in a non-soil potting mixture. This might sound good, but the down side is that these trees will dry out in the landscape quicker since the potting material does not hold water well. So, until the roots have grown into the surrounding soil, it is extra important to keep the root area well watered. Also, the root system may be potbound and will need some pre-planting work to ensure that the tree doesn’t develop girdling roots.
A mulch ring around a tree will reduce mower damage. However, too much mulch is not a good thing. Mulch should be no more than two to three inches deep and it should never touch the tree bark.
Care and Maintenance
Urban Forester Queary is very concerned about the tree topping he is seeing around town. Tree topping, the cutting of branches to stubs, is an extremely harmful pruning practice that is often done to reduce the size of a tree. Topping removes a huge amount of the leaf-bearing crown, which temporarily starves the tree. This triggers a survival mechanism, activating latent buds and forcing rapid growth of multiple shoots below each cut. These new shoots are poorly anchored and prone to breakage, so the tree can become hazardous.
Topping also causes decay due to the large wounds. Such improper care stresses a tree and a stressed tree is a target for insects and disease. Please note that it is illegal to top street trees.
When selecting an arborist to work on your trees, check for International Society of Arboriculture certification and ask for proof of insurance.
Remember that your trees are an investment. Proper care will ensure that your investment grows over time. Your beautiful trees will repay us all by making Lexington a healthy, happy place to live.
Trees –– plant them, care for them, enjoy them. Let’s get together at the Arboretum for the Arbor Day event on April 28h and celebrate our trees.