You’ll find three stories in this issue of Northern Woodlands covering the growing potential for biomass. If these improved prospects for producing more energy and other products from low grade wood are realized, it will provide opportunities for forest management that most foresters and loggers have heretofore just been able to dream about.
Particularly on small properties, the sale price of the lowest-value trees (the ones that you most want to remove to give the better trees room to grow) is too often less than the cost of cutting them and getting them to a landing. This makes life difficult for the landowner, logger, forester, and the forest. A decent, dependable market for this material would bring a sigh of relief to all and increase the economic potential of many a woodlot.
Of course, good forestry isn’t what motivates most people to contemplate putting a lot more wood into boilers. The driving force is the rapid rise in the price of oil. Those of us who are alarmed by the consequences of burning fossil fuel – even if it were cheap – have our own reasons to push for increased use of any renewable resource. The huge volume of wood that could be harvested to heat more schools, to produce acetic acid, ethanol, and other products, and to generate more electricity would allow many millions of gallons of oil and tons of coal to stay right where they are.
One worrying thing, however, is that removing trees on a large scale also removes the calcium and other nutrients in wood from the forest system. This has the potential in some instances to further deplete soil that has already lost fertility due to acid rain. Isn’t it ironic that using a renewable source of energy could itself cause harm to the same forests that acid rain has already injured?
Unfortunately, acid deposition and nutrient removal in the course of timber harvests do similar things to soil fertility and therefore have a cumulative effect. Though in most situations acid rain is considered to be the major culprit, harvesting could exacerbate the problem.
The effect would be worse if this expansion of low-grade markets resulted in an increase in the use of whole-tree harvesting. A large percentage of the tree’s nutrients, such as calcium, are in the leaves and buds. Though the bole has some calcium – and this varies by species – much more resides in the small, actively growing parts. Some landowners choose whole-tree harvesting because, with the right logger, the woods can look pretty spiffy after the job is over, with almost no mess.
Mess, however, turns out to be extremely important to forest ecosystems. All that messy dead stuff, whether from logging or natural mortality, is important. The nutrients in branches and dead trees are recycled, many animals benefit from dead wood, and all that organic matter retains moisture, which is valuable for a myriad of small creatures, such as salamanders. Decomposing wood is colonized by a succession of organisms, each of them a specialist at some stage of the demolition process. The fragments that remain are recycled to become part of the next generation of trees. If the market for low-grade wood does indeed become more stable, it would be good if the practice of turning entire trees into chips were phased out. That would be the occasion for another sigh of relief.
On the plus side, very sophisticated maps have been made for parts of the Northeast that delineate the geographical areas most at risk of calcium depletion. Using these maps can alert landowners whose soils are most vulnerable that they should consider the effect on the soil when planning to cut trees. The maps integrate data about soils with data on the amount of acid deposition an area receives, and take into consideration the influences of forest type and the composition of the bedrock.
Another possible advantage of producing more of the energy we use right in our backyards is that it might waken us to the real problem, which is that most of us use too much energy, in all forms. Could the sight of many more chip vans on the roads help bring home the environmental cost of being consumers?