March 18, 1S91.] 



Garden and Forest. 



121 



GARDEN AND FOREST. 



PUBLISHED WEEKLY BY 



THE GARDEN AND FOREST PUBLISHING CO. 



Office : Tribune Building, New York 

 Conducted by Professor C. S. Sargent. 



ENTERED AS SECOND CLASS MATTER AT THE POST OFFICE AT NEW YORK, N. Y. 



NEW YORK, WEDNESDAY, MARCH 18, 1891. 



TABLE OF CONTENTS. 



PAGE. 



Editorial Articles : — Forests and Floods 121 



The Rose-bush of Hildesheim. (With illustration.) — - 122 



Chamisso Mrs. Schuyler Van Rensselaer. 122 



Recent Botanical Discoveries in China and Eastern Burma. — IV., 



IV. Dotting Hemsley. 123 



New oh Little Known Plants:— Bessera elegans. (With figure.) 124 



New Orchids 124 



Plant Notes : — Some Recent Portraits 124 



Foreign Correspondence : — London Letter W. Watson. 124 



Cultural Department: — Chrysanthemum Queries John Thorpe. 126 



Hardy Plants from Seed" T. D. Hatfield. 



Tree Ferns IV. H. Taplin. 



Clianthus Dampieri O. O. 



Chrysanthemums T. D. H. 



L ilium Wallichianum superbum John Thorpe. 



Euphorbia jacquiniaefolia, Chorizema cordatum J. S. T. 



Correspondence : — The Wissahickon Woods J. IV. Harshberger. 129 



Winter Flowers in California B. P. Leeds. 130 



An Ancient Sunflower L. H. G. 130 



Periodical Literature 130 



Notes .' 131 



Illustrations : — Bessera elegans, Fig. 24 125 



The Rose-bush of Hildesheim 127 



128 

 129 

 129 

 129 

 129 



Forests and Floods. 



IN the River and Harbor Act, approved last year, there 

 was a clause ordering an examination of the West 

 Branch of the Susquehanna River, in the state of Pennsyl- 

 vania, with a view to ascertain (i) whether the navigation 

 of this stream could be permanently improved by the con- 

 struction of embankments or otherwise, and to ascertain 

 (2) the best practical method of confining the waters of 

 the river during the times of flood to the general course 

 of its channel. Inasmuch as the difference of elevation 

 between the mouth and the head of the West Branch, 

 covering a distance of 125 miles, is more than 400 feet, and 

 since, from physical conditions, the improvement of the 

 channel for purposes of navigation could only be accom- 

 plished by means of locks and dams, it is evident that no 

 material and permanent improvement in this direction 

 could be hoped for without an enormous expense, and the 

 engineer who has been making the examination so re- 

 ported. 



We desire, however, to call attention to the portion of 

 the report which relates to the floods of the river. We do 

 this, not because any new facts or arguments are adduced, 

 but because this is an official paper prepared by Major 

 Charles W. Raymond, who is known as an engineer of 

 great knowledge and experience, and who is altogether 

 above being biased by any sentimental considerations. 

 The basin of the West Branch of the Susquehanna oc- 

 cupies a high table-land, and has an area of nearly 7,000 

 square miles, which is about one-fourth of the drainage of 

 the Susquehanna River and its tributaries, or about one- 

 seventh of the area of the state. Major Raymond gives 

 some account of the floods of 1865 and 1889, the latter of 

 which will be remembered as signally disastrous to life and 

 property : seventy-eight persons lost their lives, and houses, 

 mills, lumber and live stock were swept away, and farms 

 and fertile bottom-lands were covered with sand and 

 gravel. As first among the causes which increase the 

 violence of such floods, Major Raymond names the de- 

 struction of forests. In this particular region the lumbering 



operations have been very extensive. In addition to the 

 ravages made by tire, it is stated that the total amount of 

 lumber, board measure, which has been cut here since 

 1862 is 5,250,000,000 feet, representing 30,100,000 logs. 

 As for the effect of lumbering operations on this large 

 scale, Major Raymond says : 



The destruction of forests from the mountain crests and 

 slopes of a water-shed is undoubtedly the principal cause of the 

 increase of the average magnitude of floods. The evidence 

 collected during the last twenty-five years, establishing this 

 conclusion, is well-nigh overwhelming, and it is verified by re- 

 peated observations, not only in the mountainous countries of 

 Europe, but also in our own land. By the removal of the for- 

 ests from the mountain slopes the ground is robbed of its pro- 

 tecting covering of roots, moss, leaves and porous soil, which 

 forms the forest-floor and serves as a natural storage reservoir, 

 holding back the water of rainfall and melting snow, and com- 

 pelling it to descend slowly to the channels. By the subse- 

 quent cultivation of the lands, ditches and drains are made to 

 facilitate the more rapid discharge from the cultivated sur- 

 faces, until the rain rushes down the hill-sides in destructive 

 torrents, gullying the ground and choking the minor lines of 

 drainage with rocks, sand and gravel, and hurrying into the 

 recipient of the water-shed volumes of water which before 

 reached it in a comparatively quiet flow. 



Colonel Torrelli affirms as the result of careful observation 

 that four-fifths of the precipitation in forests is absorbed by the 

 soil or detained by the surface of the ground, to be gradually 

 given up in springs and gentle rills, and only one-fifth of the 

 precipitation is delivered to the rivers rapidly enough to create 

 floods. Upon the same slopes and surfaces denuded of their 

 forests the proportions are reversed. That the destruction of 

 the forests in mountainous water-sheds is followed by disas- 

 trous floods, where previously such floods were unknown, is 

 not a matter of theory, opinion or probability, but is a well- 

 established physical fact. 



Other causes which increase the effect of floods are 

 enumerated ; among them artificial constructions, such as 

 bridges and dams, besides the collection of logs, lumber 

 and ice in the stream and upon its banks. But these are of 

 secondary importance. As to methods of prevention, the 

 devices of storage reservoirs and transverse barriers carried 

 across the lines of drainage seem to be inapplicable to this 

 region, for reasons not necessary here to consider, and the 

 principal reliance must be in forests. On this last point 

 the report continues : 



The method of prevention by the maintenance and planting 

 of forests upon the head-waters and upper slopes of the afflu- 

 ents of the basin depends for its efficiency upon the ability of 

 forest-covered slopes to retain for a considerable time a large 

 percentage of heavy rainfall, thereby preventing the surcharge 

 of the lines of drainage. In France, Italy, Germany and Aus- 

 tria the systematic planting of mountain slopes, as a means 

 of restoring lost fertility and preventing the inundations fol- 

 lowing the destruction of forests, is an established fact, fol- 

 lowed by results more satisfactory than the most sanguine 

 anticipations. ... As population becomes more dense and 

 the injuries from these uncontrolled floods increase, the time 

 must come when the execution of a thorough scheme of con- 

 trol will be demanded. This will require the construction of 

 numerous low dams and other inexpensive works to restrain 

 the flow of the more remote tributaries and give the lower 

 valley time to discharge the flood volume ; and, besides this, 

 new forests must be planted and maintained. 



It is no part of our present purpose to speak of the close 

 and costly survey of this region which would be necessary 

 before any intelligent work on the details of a project of 

 this magnitude could be begun. Nor is this the place to 

 consider whether the general Government should under- 

 take any work so local in its character. But the same 

 forces which have destroyed the forests which sheltered 

 the head-waters of this branch of the Susquehanna have 

 been at work with more or less energy about the sources 

 of every stream whose waters find their way from the 

 Appalachian Mountain system to the Atlantic Ocean or the 

 Gulf of Mexico. Between the Adirondacks and Alabama 

 is a continuous line of such basins as that surveyed in 

 Pennsylvania by Major Raymond, and more serious still is 

 the threat of devastation from the mountain systems of the 

 west, with their greater altitude and steeper slopes. 



