Usually, we don’t set out to kill a tree unless we need it removed for a specific reason. The tree might be too old; it might be in the way of construction. Or, as is the case with our backyard ash, it might be too large for the space.
However, the purpose of the provocative title is to grab your attention and discuss how folks unintentionally kill trees. According to the Arbor Day Foundation, “Nationwide, about 20 percent of all new street trees die soon after being planted.” Street trees are usually considered to be those planted between the sidewalk and the street in urban areas. However, the following information applies to trees planted in yards, parks, and playgrounds. Much of the following information is from the Arbor Day Foundation.
Planting: To kill a tree before you ever get it in the ground, leave it out where the sun and wind will dry out the roots and foliage and then don’t water it after planting. Some folks who feel they are helping a tree plant it deep, in a narrow hole, pack the soil tightly around the roots, and then heavily water it. Changes are the tree will slowly drown and suffocate.
Young trees: Letting trees and surrounding soil dry out will kill a tree – a real problem in Alamosa where we typically have dry soil and don’t receive much precipitation. Well-intended people will sometimes stake a tree very tightly hoping it won’t topple in our strong winds from the southwest. The problem is trees need to sway a bit to develop strong roots. A few times people who have had a young tree die say they gave it lots of fertilizer or fresh compost to kick start its growth. Planting a tree stresses it. Adding too much ‘nutrition’ is similar to feeding a flu patient a big streak -- roots and leaves can burn.
In parks or lots with large lawns, the biggest cause of young tree death that I’ve seen is from weed whackers or lawn mowers cutting into the bark near the base of the tree. In parking lots, trees need to be protected from vehicle bumpers. In Alamosa’s railyard parking along 6th Street, railroad ties keep cars from running into the trees.
Your young tree is not a hitching post! Chaining bicycles or dogs to a young tree will cut the bark. Did you know if you cut the bark all the way around the tree in an inch or two wide swathe it will kill the tree? Bark doesn’t heal like human skin. The bark is the conduit between the roots and the leaves; if the path is severed, the tree will starve.
Trees of any age: Your tree need a trim? Want to do a thorough job so you don’t have to do it again for many years? If you prune too much, there won’t be enough foliage to support the underground root structure (rule of thumb – never prune more than one-fourth of the live crown of the tree in a single year).
If you make sure your tree doesn’t receive water and oxygen, it will die. I remember a very nice lady who owned a bed and breakfast where we stayed in Colorado Springs. She bemoaned the death of a large tree at the back of the building. She just couldn’t understand why it seemed to suddenly die. What they’d done is pave the entire backyard (including right up to the tree) with asphalt to provide better car parking. She didn’t grasp the idea that the tree died of starvation and asphyxiation.
Construction can also be a big killer. Trench through root zones, cutting as many large roots as possible. Remember, most of a tree’s roots are in the top two-three feet of soil and they spread out. Running large machinery over soil can also kill trees. The pounding compacts the soil making it difficult for air and water to penetrate and reach the roots.
So what can you do to avoid killing a tree unintentionally? Please check out the ‘Planting & Care’ tab at the AlamosaTrees.net website. You can also download the new Alamosa Tree Board “Tree Maintenance & Planting” brochure or pick one up at an Alamosa greenhouse or nursery. The Alamosa Tree Board developed the brochure and funds from a Colorado Tree Coalition grant paid for the printing.
“I think that I shall never see a billboard lovely as a tree. Perhaps, unless the billboards fall, I’ll never see a tree at all.” Ogden Nash