720 EXPEEIMENT STATION KECORD. [Vol. 35 



cast up by water a control shelter of hardy shrubs must be set as close as possi- 

 ble to the winter line of high water and ice. An artificial barrier of drift mate- 

 rial and wood forms a splendid protection and justifies considerable expense lO 

 establish it. . . . 



" There are two general plans of operation in the work of sand control. The 

 'shelter belt' or 'barrier' system is suitable to private owners. It may be so man- 

 aged as to enable the man of limited means to do systematically a portion of the 

 work each year until the whole blow area is under permanent forest cover. The 

 ' entire cover ' system calls for heavy expenditure in labor and materials but 

 has as its aim the completion of the work over the whole area in a single season." 



Contribution to the knowledge of the weathering of podzol sells of middle 

 Norrland, O. Tamm (Bui. Geol. Inst. Univ. Upsala, 13 (lOU-lo), I, pp. 183-204, 

 figs. 2; abs. in Chem. Ahs., 10 {1916), No. 9, pp. 1243, Jf2^^).— Studies' of samples 

 of eight profiles of podzol soils in middle Norrland, Sweden, are reported. 



The chemical composition of unweathered soils in the region, with perhaps 

 the exception of clay, appeared to be very uniform. The chemical and min- 

 eralogical compositions of soil layers weathered by raw humus acids (blei- 

 cherde) were very uniform. The chemical processes involved in raw liumus 

 weathering of soils were found to consist of decomposition rather than trans- 

 formation of the minerals. Apatite and dark colored minerals, such as biotite 

 and hornblende, were the most easily soluble. On the other hand, feldspars 

 were relatively little attacked. A marked formation of kaolin was not observed 

 in cases where the feldspars had been relatively much attacked. An estimate 

 of the amount of change in the original materials brought about by the forma- 

 tion of bleicherde showed that approximately 7.5 per cent of the bases in 

 percentage of original material were dissolved. 



A list of 11 references to literature bearing on the subject is appended. 



Some problems of the study of forest soils, G. A. R. Bobghesani {Internat. 

 Mitt. Bodenlc, 5 (1915), No. 3, pp. 225-231, fig. 1).— This is a critical review 

 of the question of forest soils, with particular reference to the useful adapta- 

 tion of tree kinds to different soils and the function of the covering of forest 

 litter in the maintenance of forest soils. A list of references to literature 

 bearing on the subject is appended. 



Chemical and biological notes on cherry orchard soils, A. Hauvey and C. H. 

 HooPEE {Gard. CMon., S. ser., 57 {1915), No. US4, PP- 308, 309; nhs. in Internat. 

 Inst. Agr. [Rome], Mo. Bui. Agr. Intel, and Plant Diseases, 6 {1915), No. 8, p. 

 1067; Chem. Abs., 10 {1916), No 9, p. 1243).— Chemical and mechanical analyses 

 of several samples of orchard soils to determine whether the yield of cherries 

 is a question of chemical and mechanical composition or one of pollination are 

 reported, the results of which are taken to indicate " that very little value can 

 be assigned to figures obtained either in the chemical or mechanical analy- 

 sis. . . . 



" The conclusions to be drawn from observations on the growth and cropping 

 capacity of the cherry trees compared with the analysis of the soils would seem 

 to be that favorable soil influences the actual growth of the tree, but not 

 necessarily its fruiting capacity. The cherry being by nature a free flowering 

 tree, if year by year it does not crop the fault is probably the lack of suitable 

 cross-pollination rather than some fault in the soil." 



Investigations on tobacco soils, B. T. P. Barker {Jour. Bath and West and 

 South Counties Soc, 5: ser., 9 {1914-15), pp. 129-181).— Analyses of a series of 

 samples of American and African tobacco soils are reported. 



" The American soils as a group may be described as very coarse-grained 

 sandy soils of feeble water-holding capacity and poor in all the elements of 

 plant food. . . . The African soils, on the other hand, are sandy soils of good 



