City Forest Farming
One of the bright spots in our fumbling, bumbling economy is the progress of urban and suburban farming, especially in connection with farmers’ markets. But there is another aspect of this coming together of city and country that needs more innovative thinking. I was traveling through Shaker Heights and Cleveland Heights in Cleveland, Ohio, recently and was struck by how much of this beautiful, old, well-heeled residential area is really old growth forest with houses in it. And I mean real, old growth forest—lots of huge trees towering over the castle-like residences so densely that the houses are almost hidden from view.
My first thought was how much people love trees because there is considerable risk involved when these trees inevitably die or age enough so that storms drop them on the houses. My next thought was to try to calculate how much wood was growing here in this urban forest which will probably end up in a landfill. Oddly enough, the answer to both potential problems is the same.
Let us take, just for discussion purposes, five square miles of this kind of urban forest. A mile square is 640 acres, so five miles square would be 3200 acres. An acre of established woodland can produce a cord of wood a year without diminishing itself, so the experts agree. With good forestry practices it can do better than that, but let’s go with that figure. Let’s assume that every acre in this old growth urban forest would produce half a cord a year because the houses and lawns take up some of the room. So this tract in Cleveland could be producing 1600 cords of wood a year. At let’s say $200 a cord (more than that as a replacement for heating oil right now), that’s $320,000 a year.
Now try to imagine how many wooded urban acres there are in this country. We’re talking millions and millions and millions of dollars in wood mostly going to waste due to a lack of planning and management. The main problem is that we don’t think in tree time. Humans are lucky to live 80 to 90 years. The life cycle of trees is twice that at least, but it is, nevertheless a cycle. We tend to think of our beloved trees as monuments but they are living things. We should be planting them and harvesting them on a schedule of about eighty to a hundred years to take advantage of their value as lumber or fuel while avoiding most of the possibility of storm damage. The issue is increasingly pertinent, especially now that power companies are again thinking seriously of using wood for some of its electrical generation.
The first management plan should involve the choice of trees used for urban forests. Maples and oaks, for example, are just as pretty as smaller ornamental trees but contain more BTUs for fuel and better wood for lumber. But even small trees can make good firewood, and some of them, dogwood for example, are high in BTUs or for specific wooden products. Persimmon wood used to be used for sidewalk and road pavers almost as durable as brick. It also makes beautiful golf drivers.
The supply of this kind of wood is only going to increase tremendously. Newer subdivisions and their trees are in the process of becoming the mature urban forests of tomorrow. Older village and town residential areas are already facing lots of problems because of storm damage and power outages as their trees grow bigger and older. Starting now for a planned, orderly cycle of harvesting old trees and growing new ones, of varieties known for good lumber or fuel wood products, will at the very least alleviate the cost of removal and could eventually become a profitable enterprise. It will also generate jobs. Already there is a big increase in the number of tree removal businesses, increasing use of bucket hoists and other tree handling equipment. You may have noticed, if you live in an urban forest, the appearance of a new job skill. A new brand of tree trimmer has come along who swings from tree to tree on ropes, able to remove huge tree limbs over houses with a chainsaw, piece by piece, in places where no other removal method is feasible.
Since residential home owners almost always prune their trees as they grow, they can start doing it to produce clean-limbed, valuable logs for lumber sales. This kind of urban forest farming is a totally win-win situation because although the rewards of selling the wood may be years and years away, the reward of enjoying the trees as they grow is ongoing and the environmental benefits of those trees taking in carbon dioxide and releasing oxygen are lifesaving. City planners have often proposed the idea. When are we going to start listening?
What do you think? Leave a comment below.
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