Regular Seed Forest or High Forest. In the system already mentioned above of seeding from the side, the trees near the cut areas are depended upon to seed these areas. Moreover, no especial pains are taken to preserve the forest floor and the forest cover. But all trees do not bear seeds annually, nor do their seedlings thrive under such conditions. In other words, in some forests especial pains must be taken to secure reproduction, and the forest conditions must be maintained with special reference to the growing crop. For this purpose, the cuttings take place thru a series of years, sometimes lasting even twenty years. These reproduction cuttings have reference, now to a stimulus to the seed trees, now to the preparation of the seed bed, now to the encouragement of the seedlings. Then later, the old crop is gradually cut away. Later still, in twenty or thirty years, the new forest is thinned, and when it reaches maturity, perhaps in one hundred or two hundred years, the process is repeated. This is called the "Regular Seed Forest." It produces very valuable timber, and has been used for a long time in Switzerland, especially for beech and balsam.
The system is complicated and therefore unsafe in ignorant hands, and the logging is expensive.
Two-storied Seed Forest. A modification of the system of Regular Seed Forest is the planting of another and a tolerant species of tree under older intolerant trees to make a cover for the soil, to prevent the growth of grass and weeds, and to improve the quality of the upper growth.[2]
An illustration of a natural two-storied seed forest is shown in Fig. 126.
No. 126. Two-storied Seed Forest. Fir under Beech, Germany. U. S. Forest Service.
Planting. The planting of forest trees is a comparatively unimportant part of modern forestry. It is a mistaken idea, not uncommon, that the usual way of reproducing forests is to plant trees. It is true that in the pineries of North Germany and in the spruce forests of Saxony, it is common to cut clean and then replant, but it is absurd to conclude, as some have done, that forestry consists of planting a tree every time one is cut. Even if planting were the best method, many more than one tree would have to be planted for each one cut, in order to maintain the forest. So far as America is concerned, not for a long time will planting be much used for reproduction.
The greater portion of American woodlands is in the condition of culled forests, that is, forests from which the merchantable trees have been cut, leaving the younger individuals, as well as all trees belonging to unmarketable species. Even on the areas where the lumbermen have made a clean cut of the original timber, new trees will come up of themselves from seeds blown from the surrounding forests or falling from occasional individuals left standing. (Bruncken, p. 133.)
The usefulness of planting in America is mainly for reclaiming treeless regions, as in the west, and where timber is high priced. The area of planted timber in the Middle West aggregates many hundred thousand acres, once waste land, now converted into useful woods.[3]