With high energy costs, some homeowners are turning to wood for heat. I’m one of them.
Fortunately, the farm has a number of volunteer trees that can be used for firewood. The most common species is Siberian elm but there are also some hackberry and mulberry. Though there may be enough volunteer trees to supply the need, better firewood trees would reduce the time and effort required to supply the wood needed. Actually, storm-damaged trees or trees in the wrong place will always provide a measure of the demand but a significant supply could be supported by a firewood “plantation.”
Plant species is an important consideration as not all trees have the same density and therefore heat value. The greater the dry weight, the better. The highest value for trees commonly found in Kansas is Osage Orange (Hedgeball tree) at 4,800 pounds per cord. Osage orange has a gnarly growth habit and a nasty set of thorns. This species also sparks which isn’t a problem in a wood-fired boiler but certainly would be in an open fireplace.
Black locust is next with 4,200 pounds per cord. Black locust is a fast grower and also has excellent burning qualities and makes a nice bed of coals. However, it is hard to split, suckers, and has some relatively small thorns, especially on young trees. Bur oak and red oak come in at 3,800 and 3,500 pounds per cord respectively but are not fast growers. Mulberry, however, has the same weight as red oak but grows more quickly. Silver maple has less heat value (3,000 pounds per cord) but is a very fast growing tree.
Black locust would be my first choice for this purpose though you may wish to plant rows of several species. However, each situation is different and another species may work better for you. So how do you set out your plantation? Dr. Wayne Geyer, one of our retired forestry professors, has done many woody biomass studies over the past 35 years. Following are some recommendations that have come out of his studies.
– Plant locust a few rows in from a field edge to reduce suckering in the field.
– Plant on a close spacing, 4 to 6 feet apart. This maximizes yield and reduces side branching.
– Control weeds the first two years.
– Harvest every 5 years, most trees will resprout and can be reharvested.
– Plant about 1 acre per year for 5 years if you wish to supply the majority of the firewood needed to heat your home.
By: Ward Upham