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MOSSES AS A FACTOR IN LAND CONSERVATION 



A. J. Grout 



It has long been recognized that the mosses, particularly the Sphagna, play 

 an important part in holding back the rainfall in forested regions, thus prevent- 

 ing floods and droughts. Indeed the mosses and the humus that collects in and 

 around their continually growing and continually dying stems is the one most 

 important factor in this work, the trees serving principally to protect and shade 

 the mosses. 



Little, if any, attention has been paid to the work of mosses in preventing 

 and delaying erosion, though the author believes that investigation will show 

 that this is no mean factor in the problem. 



In the North Carolina mountains where the terrific downpour of the summer 

 showers approaches the New England "cloudburst" in intensity every few days, 

 one will find little peaks and plateaus on a freshly eroded bank that will remind 

 him of a chip on a snowbank in spring. On examination the top of the eleva- 

 tion will be found to be covered with a fine network of moss protonema, which 

 has protected the soil beneath from the rain in the same way that the chip pro- 

 tected the snow from the spring sun. Again, in all the mountain brooks the 

 beds are covered with a more or less extensive mat of aquatic mosses except in 

 the swiftest places. Hygrohypnum, Brachythecium, and Amhlystegium in num- 

 erous species clothe stones and soil along the bed and banks of the stream, all densely 

 packed with sand and soil rescued from the hurrying waters in their mad spring 

 rush, so that not only is the bed of the stream not eroded by the rushing water, 

 but is even built up by it. 



EXCHANGE DEPARTMENT 



(To Society Members Only — For Postage.) 



Frank Dobbin, Shushan, New York. — Tetraplodon australis Sulliv. and 

 Lesq. Collected at North Brookfield, Mass. 



Mr. Edward B. Chamberlain, 38 West 59th St., New York City. — Philo- 

 notis fontana (L.) Brid. c. fr. Philonotis tomentella Mol. st. Sent from Finland 

 by V. F, Brotherus. 



Mr. George B. Kaiser, 524 Locust Ave., Germantown, Pa. — Plagiothecium 

 striatellum (Brid.) Lindb. c. fr. Collected in Philadelphia, Pa. Hygrohypnum 

 dilatatum (Wils.) Loeske; Alisa calif arnica Sulliv. Collected in Washington by 

 A. S. Foster. 



Mr. E. J. Winslow, Auburndale, Mass. — Paludella squarrosa (L.) Brid. 

 Collected in Vermont. 



Judge W. W. Calkins, Berwyn, 111. — A number of marine algae mounted — 

 some named. 



C. C. Kingman, 11 Lowell St., Reading, Mass. — Fr ullania Bolanderi Aust., 

 Asterella Palmeri (Aust.) Und. Collected in southern California. 



