Ekki Wood Environmental Issues
INTRODUCTION
Concerns about the effects of human actions on the health of our environment are playing an increasing role in every-day decision making by individuals and by public authorities. The effects of extraction of timber from the forests and the continued use of treated softwood are but two of many current environmental concerns. These two concerns are discussed below.
This paper identifies and briefly discusses a number of issues that should be of interest to both proponents and critics of the use of treated and untreated timber. Environmental issues concerning EKKI hardwood from various perspectives are identified.
PHYSICAL CHARACTERISTICS OF EKKI HARDWOOD
Before going into the various environmental concerns it is important to understand some leading physical characteristics of EKKI wood. These characteristics limit the use of EKKI wood to relatively few exterior applications. In brief, EKKI wood is extremely hard, tough and heavy. It has a coarse, interwoven/interlocked grain structure. This grain structure provides exceptional toughness, enhances its resistance to splitting and provides great resistance to abrasion, thereby contributing to a long service life. It also prevents it from being used for virtually any interior applications because of its tendency to warp, bend and twist in relatively small/thin cross-section.
TYPICAL APPLICATIONS OF EKKI WOOD
The typical grain structure described above creates a tendency of small cross-section pieces to warp and bend when they dry. For this reason EKKI wood is typically not used in section smaller than about 35 mm and it is not used at all for any interior application. In large cross-section timbers, such as typically used for marine and hydraulic purposes, the grain direction averages out over the cross-section of the piece and such EKKI timbers are stable. Hence EKKI hardwood is virtually exclusively used for heavy duty exterior applications such as in the marine and hydraulic environments, foot/pedestrian bridges etc.
Ekki can only be machined with modern power tools. It is much too hard and too tough to work with hand tools. Also, it cannot be nailed without pre-drilling. This, in addition to its tendency to warp in small section renders EKKI hardwood useless as a utility wood. For the same reason, it cannot be used for furniture or any other kind of interior application. This mitigates against the logging of small EKKI trees and enhances the probability of long term survivability of this species and continued long-term availability.
ACTIVE CONSERVATION MEASURES
As an active conservation measure imposed by the governments of the exporting countries EKKI trees are selectively logged and only logging of mature, large diameter is permitted. This measure, and the fact that small diameter EKKI trees have no commercial value, ensures that many more trees capable of sustaining the species remain in the forest than are removed from the forest.
LONG SERVICE LIFE MINIMIZES REQUIRED VOLUME
There are important additional reasons why the choice of EKKI wood is environmentally sound. Because of EKKI's superior strength and toughness, for a given job much less EKKI wood is required than alternate timber types, which in the North American context typically would be a softwood species such as Douglas Fir. This fact holds true for the initial installation and over the life of the facility. Therefore, the use of EKKI wood reduces the total volume of timber required for any particular application over the entire life of a facility. The use of longer lasting timber reduces the logging pressure on the forests of the world.
NO CHEMICAL WOOD PRESERVATIVES
Of increasing concern are the long-term effects of chemical wood preservatives (creosote, ACA, ACC etc) on the environment and on public health. For this reason, the number of civil jurisdictions that regulate the use of treated wood, and for certain applications prohibit its use, is increasing. EKKI hardwood requires no preservative treatment and it is therefore entirely benign to the environment, the worker and the public.
Unlike working with treated wood, there is no need for re-treatment of field-cuts, a messy procedure that is seldom done well.
NO DISPOSAL PROBLEMS
Increasing numbers of civil jurisdictions prohibit disposal of treated waste wood and retired treated wood in its landfill sites. To add to the problem, treated wood cannot be safely burned. Frequently expensive measures have to be taken to manage and store retired treated wood. Because EKKI is naturally durable it requires no preservative treatment of any kind and upon retirement, EKKI hardwood poses no storage problems and no disposal problems. If necessary, it may be safely burned.
REDUCED ENERGY CONSUMPTION
The manufacture of structural materials consumes man-made energy. Man-made energy production creates a burden on the environment in various ways such as the flooding of land for hydroelectric development, air and water pollution from fossil fuel burning plants or nuclear waste disposal/storage from nuclear power plants. It can be shown that the production of structural materials including all metals, plastics/polymers and concrete consumes a great deal more man-made energy than timber.
NO HARMFUL EFFLUENT AND BY-PRODUCTS
The conversion of EKKI logs to timber products produces no harmful effluent or by-products of any kind.
CARBON DIOXIDE ABSORPTION AND STORAGE
Excess carbon dioxide is considered to be a harmful contaminant of the environment. Vigorous growth of all types of trees absorbs such carbon dioxides. Therefore, in support of atmospheric carbon dioxide reduction, the growth of vigorous young wood should be encouraged and the service life of harvested timber should be maximized. As noted above, young EKKI trees are not logged and have many years of growth during which they continue to absorb atmospheric carbon dioxide. Eventually, when the trees are large and mature they are logged, clearing growing space for new young trees. The long service life of EKKI wood and its subsequent extremely slow natural decay ensures a very long carbon dioxide retention time.
CONCLUSION
The use of EKKI timber is mainly limited to marine, hydraulic and selected other exterior applications. This fact, taken together with the other issues identified in this paper suggests that the argument can be made that the use of EKKI wood for such applications is much more benign to the environment than the use of treated timber types, and possibly other materials, for the same application.