The Blights Of Coniferous Nursery Stock PDF Download

Excerpt from The Blights of Coniferous Nursery Stock A feature of sun scorch in nurseries, as well as in the older trees described by Stone,1 is that the absorbing portions of roots die at the same time as the tops or even before. This indicates that the leaf and stem tissues can stand water loss better than the vegetative tissues of the roots. Especially in the case of transplants the cam bium of the entire root system, or at least of the outlying portions of it, has been found to be dead and brown. By the time the needles show the first signs of yellowing, a large part iof-the root cambium is already gone. This especially early death of a large proportion of the root systems of the scorched transplants is probably due to the fact that a tree in the transplant bed has a smaller root system in proportion to its transpiring surface than a second-year seedling would have. When only a part of the needles on a. Plant are killed it appears that the damage to the root is more extensive than to the tops. This is indicated by the fact that a plant which has lost part of its needles in an attack of this disease is more likely to succumb to later attacks of the same nature. Evidently the reduction in transpiring surface caused by the first attack is more than counter balanced by the reduction in absorbing surface. 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.