NOTES AND COMMENT 



The work carried out by Shantz in 1911 relative to the value of 

 natural vegetation as an index of crop possibilities in the Great Plains 

 region, has been extended, with the collaboration of Kearney, Briggs 

 and others, to the Great Basin. The Tooele Valley, on the south shore 

 of Great Salt Lake, has afforded a suitable location for the work, which 

 has been reported in the Journal of Agricultural Research (vol. 1, p. 

 365). Seven distinct vegetations are found in the valley, including 

 pure stands of Artemisia tridentata, of Kochia vestita and of Airiplex 

 confertifolia, as well as mixed stands in which the above and other 

 species are concerned. The physical texture of the soils underlying 

 these vegetations was found to determine the acquisition and retention 

 of water, and to determine the character of the vegetation when taken 

 in conjunction with the amount and position of alkali in the soils. 

 The existence of farming lands, with and without irrigation, in all parts 

 of the Tooele Valley, has made it possible for the authors to make very 

 specific recommendations as to the possibility of agricultural success on 

 land occupied by the several vegetations. 



There have been much more definite results in the study of natural 

 vegetation as an indicator of whether agriculture is possible or is not 

 possible, than there have been in its use to determine the particular 

 crop which may best succeed where a given plant cover exists. There 

 has also been a striking difference between the investigations of this 

 character which have been carried out in semi-arid or arid regions, 

 where the vegetations are strongly differentiated, and in humid regions, 

 where they are more uniform even on soils which are widely dissimilar 



• 



Mr. R. Lloyd Praeger, of Dublin, has written a booklet entitled 

 Weeds (Cambridge, University Press), a popular and instructive ac- 

 count of the Irish ''plants growing in places where man does not want 

 them to grow." Much is said about the means of dispersal of weeds 

 and the book is brought down to the last minute by the suggestion that 

 aeroplanes may now become effective distributors of seeds over long 

 distances. A large number of original field experiments on the behavior 

 of weeds are suggested, offering an interesting line of work to the teacher 



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