C. Forests of the usa

The amount of timber resources of the USA is second only to Russia. Forest land occupies one third part of the United States area.

There are over one thousand species of trees in the United States. In Europe (without Russia) there are less than one hundred. England has about thirty and France thirty-five. Out of the one thousand kinds of trees in the USA only about one hundred have much commercial value as lumber. Of these about sixty are hardwoods and about forty are softwoods, but only fifteen hardwoods and fourteen softwoods are extensively used for lumber, plywood, pulpwood and construction timber.

The softwoods are the oldest family of trees in the United States. The commercial softwoods of importance are: southern yellow pine, Douglas fir, hemlock, Sitka spruce, larch, and white fir. Hardwoods which are broad-leaved and usually shed leaves in autumn furnish about 20 per cent of US commercial wood products. They are oak, maple, birch, beech and others.

Most part of the forest land is privately owned and consists of small parks and farms. The care of these forests lies on the small owner. There are 146 national forests furnishing 159 million acres in the United States (figure 2.3).

D. Forests of Canada

The most important forest trees in Canada are the spruces (figure 2.4). About one third of Canada’s timber is spruce. Its wood is used for pulpwood, lumber and plywood. Second only to the spruces are two-needled pines. These pines furnish 11 per cent of Canada’s standing timber volume. Third in importance are the true firs, of which the most distributed is the balsam fir. Its wood is commonly cut as pulp-wood and to a lesser extent, as sawn goods. Next is a family of broad-leaved deciduous trees - aspen and poplar.

F

Figure 2.4

ifth among Canada’s forest trees is the hemlock. Western hemlock is a valuable pulpwood species; eastern hemlock is the main commercial source of tannin, while the wood is used for railroad ties, lumber and pulp. Douglas fir is used extensively for lumber, plywood and construction timber. Next in order are the cedars. Their wood is light and resistant to decay. In virgin forests they reach heights of 150-200 feet and diameters of 8 to 10 feet. Their wood is used for lumber, poles and posts. Finally there are the birches. Most distributed is the white birch which grows widely throughout Canada. The most important hardwood tree in eastern Canada is the yellow birch. Its wood is much in demand for flooring, furniture veneer and railroad ties. Canada is indeed fortunate to possess such a variety of useful tree species. The pine and spruce in the east, and Douglas fir, cedar and hemlock have won for Canada its position as the world’s leading nation in forest products trade. The sugar maple is one of the Canada’s best known symbols and the leaf appears on the country’s flag.

E. Australian forests

The Australian forest flora consists mainly of evergreen hardwoods, mainly eucalyptus or gum tree (figure 2.5). Of the 700 species of the genus eucalyptus, 95% occur naturally in Australia. There are 40 palm species in the country. A limited area, about 5 per cent of the forest land, has favourable soils and rainfall and contains forests of the Indonesia type, and forest area of similar size is covered by conifers, mainly cypress pine.

The conifer forests are exhausted and do not meet the domestic demand for lumber, and large quantities have to be imported from New Zealand and North America. To some extent this deficit will be covered by large – scale plantations of exotic pines. The wild eucalyptus forests form the base of an important lumber and pulping industry. They are mostly old and on average rather slow-growing. On good sites, however, many of the eucalyptus species are capable of very high production and some have become important for plantations in other parts of the world.

Figure 2.5