ARCTIC PLANT GEOGRAPHY 1 49 



that the quickest way to thaw out a soil is to run water through it by 

 sinking pipes with openings along their sides into the frozen soil, 

 so that water can be forced into and made to circulate through the 

 frozen strata. This is an important practical matter, for such towns 

 as Valdez, Alaska, are built on alluvial glacial fans under which there 

 is permanent ice. More such studies should be made like the recent in- 

 vestigations of Keranen and Kokkonen in Finland and Hogbom in 

 Sweden. 22 Such investigations of frozen soils should be correlated with 

 the fact, which has been known for some time, that large trees will grow 

 on the shallow morainic deposits actually mantling blue, glacial ice. 

 Cooper's field work^^ in Glacier Bay, Alaska, has made known to us 

 in detail this interesting phenomenon. Last summer (1926) the writer 

 photographed and studied plants growing on the green ice covered 

 with morainic material at the foot of Allen Glacier on the Copper 

 River and Northwestern Railway. A detailed investigation of this 

 phenomenon is of importance, as it suggests that plants (even trees) 

 might have existed at the foot of glacial ice during the maximum 

 refrigeration of the continents, for we are beginning to suspect that 

 the Glacial Period did not have such extremely low temperatures but 

 a kind of precipitation which resulted in the general and continental 

 accumulation of snow and glacial ice. 



Study of the Tundra As Reindeer Pasture 



Stefansson^* has recently emphasized the importance of the utiliza- 

 tion of the "Barren Grounds," or tundra of Canada, in the raising of 

 caribou for the market. The caribou feeds largely on the reindeer 

 lichen and other tundra plants, especially in winter, when it paws 

 away the snow to get the lichens underneath, also using the spadelike 

 downward-projecting front prongs of its antlers to shovel the snow. 

 In these Arctic ranges the mistakes of overcropping which have been 

 made on the prairie plains of the United States should be avoided. 

 Our nation should have learned by bitter experience that scientific 

 study of the vegetation of the open range would have prevented its 

 deterioration. Before we have a repetition of the same economic waste 

 on the tundra, a detailed study of its plants, especially the lichens, 

 should be made and an experimental investigation of the methods of 

 reproduction. The distribution and abundance of the various tundra 



22 J. Keranen: Uber den Bodenfrost in Finnland, Mitt. Meteorol. Zentralanstalt des Finnischen 

 Staates, No. 12, Helsingfors, 1923. 



P. Kokkonen: Beobachtungen iiber die Struktur des Bodenfrostes, Acta Forestalia Fennica, 

 No. 30, pp. 5-54, Helsingfors, 1926. 



Bertil Hogbom: Uber die geologische Bedeutung des Frostes, Bull. Geol. Instn. Univ. ofUpsala, 

 Vol. 12, pp. 257-390, Upsala, 1913; idem: Beobachtungen aus Nordschweden uber den Frost als 

 geologischer Faktor, ibid., Vol. 20, pp. 243-280, 1927. 



23 W. S. Cooper: The Recent Ecological History of Glacier Bay, Alaska, Ecology, Vol. 4, Brooklyn, 

 N. Y., 1923, pp. 93-128, 223-246, 355-365. 



24 Vilhjalmur Stefansson: Polar Pastures, The Forum, Vol. 75, New York, 1926, pp. 9-20. 



