Excerpt from Concerning the Enhancement of Increment: Which Takes Place in Tree-Forest After Heavy Thinnings or Partial Clearance, for the Purpose of Permitting the Timber Crop to Have a Fuller Enjoyment of Light, Air, and Warmth Spruce an cl Silver Fir. - The way for partial clearance should be paved by preliminary operations carried out about the 25th to 3oth year in such a manner as to let -the predominating poles have a clear space of 2 or 21} feet around the crowns, these favoured individuals standing about 15 to 17 feet apart, and all the rest of the crop being thinned out in the ordinary manner customary in pure forests without interruption of canopy. During the 30th to 50th year, when the influence of this measure has made itself apparent in the re-formation of close canopy, the main partial clearance takes place in somewhat similar manner, the stems between the favoured individuals being freely thinned so as to permit of the formation Of an undergrowth either naturally, or where necessary artificially, wherever the minor portion of the crop is of itself insufficient to protect the productive capacity of the soil. When the favoured stems have at breast-height a girth of about 36 to 40 inches, which they should attain between the 60th to 8oth year, the marketable trees can then be gradually cleared away on the same principle. Another method, practised in the neighbourhood of Salzburg in Western Austria in mixed forests consisting of spruce, silver fir, and beech, consists in carrying out the thinnings once every 10 years after the crop has attained 30 years of age, and making them heavier each time the operation is repeated, until the main partial clearance is made about the 60th or 70th year, leaving 120 to 160 stems per acre, all of them conifers and in energetic growth. Under such a crop natural reproduction can easily be effected, so that about 20 years later the standard trees are of large marketable dimensions, whilst the young growth may vary from 5 to 15 feet in height. On the removal of the standards the blanks thus formed in the new crop can easily be filled up artificially, and may be advantageously utilised for the formation of mixed forests by the introduction of other species. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.