228 POLAR PROBLEMS 



Some writers on Arctic climate and vegetation have discussed 

 certain districts as being deficient in vegetation because lacking in 

 rain. They seem to be analogizing from the tropic and temperate 

 lands which they know and assuming the vegetation to be suffering 

 thirst because the rainfall measures small in centimeters. But it is 

 doubtful whether such thirst can befall anywhere in the Arctic. I 

 have frequently dug into the ground in the Canadian sections where 

 the books say that the vegetation is suffering from lack of water and 

 have never failed to find, a few inches or a foot down and well within 

 reach of the plant roots, a frozen earth which, when thawed, became 

 mud or was at least extremely damp. Imagine, then, a plant growing 

 here in soil that ordinarily thaws five inches by August. Assume a 

 particularly dry season with constant glaring sunshine and the 

 warmest winds possible in that district. Conceivably this might 

 double the thaw to ten inches, whereupon the extra five inches thawed 

 would become mud from which the plants could draw moisture. Thus 

 they certainly would not suffer from thirst that year; more likely it 

 would be a favorable year for them. 



But it seems a priori that a succession of such extremely dry 

 seasons would exhaust the water supply farther and farther down.^^ 

 The simplest reply (and one sufficient until definite observation 

 contradicts it) is that of all the places examined by us through many 

 years in the supposedly too-dry areas, none was found that showed 

 the assumed desiccation. 



Study of Proper Grazing Methods 



One of the outstanding climatic features of the Arctic, then, is 

 that drought, as understood elsewhere, does not exist. This is impor- 

 tant for the grazing wild animals and for domestic herds that have 

 been or may be introduced. For if you use husbandry methods 

 analogous to those that prevent overgrazing elsewhere, then you can 

 in the Arctic rely on the same amount of vegetation per year every 

 year forever. A square mile that supports twenty-five reindeer in 

 Alaska this 3^e'ar will, if that limit has been set by a competent student 

 of grazing, support twenty-five reindeer indefinitely.' 



This does not say that a study of climatic conditions affecting 

 possible variation in Arctic vegetation is not necessary. Rather it 

 points out that such study will have a special interest, for the chief 

 cause of variation elsewhere (droughts) is either eliminated or so 

 changed in local application that a new set of conclusions will have to 

 be drawn. 



Arctic grazing problems have already been attacked by the U. S. 

 Biological Survey. The quantity figures for one year serve roughly 



12 For a discussion of how the cultivation of fields may change the natural situation see the writer's 

 'The Northward Course of Empire," New York, 1922, p. 212. 



