756 EXPERIMENT STATION RECORD. 



in Wisconsin is described, and the results of several years' experiments at the station 

 on muck soils ; E. S. It.. 16, p. 29) and of preliminary experiments daring one year 

 on peal soils are summarized. The general conclusions drawn are: 



•• I The marsh Boils of Wisconsin belong to two distinct type-. | 1 i The black 

 marsh or muck soils usually underlaid by day and I 2 i the peat or moor soils usually 

 underlaM by sand. 



" 2 The Mark marsh Boils are fertile except in comparatively small areas where 

 they require potash. 



The peat soils, especially where underlaid by Band, will require both 

 and phosphoric acid or an application of manure to make them productive. 



■■ 1 The results of the experiments made this summer do not indicate that the 

 use of lime on this s<>il will be especially beneficial. This is a matter, however, 

 which needs further study. 



■■ 5 These soils are adapted, on account of the large amount of nitrogen they 

 contain, to such crops as corn, rape, and the bay grasses. The danger of injury 

 from frost, however, lessens somewhat their adaptability to corn. 



'• 6) The injury from frost can be greatly lessened by drainage." 



On the structure of cultivated soils, A. Delage and H. Lagattj i ' 'ompt. Rend. 

 Acad. Sci. [Paris], . -V... .-_;. rl ,. in;.:. 1044).— The author advocates micro- 



- pic examination, with polarized light, of layers of fine earth of 0.01 mm. in thick- 

 ness as a valuable means of determining the character and composition of soils. His 

 observations indicate that soil proper is the result of di-aL r L r rei. r ati'>n rather than 

 decomposition oi the mineral constituents of the original rocks; that is, the feldspar. 

 quartz, mica, calcite, apatite, etc.. found in the tine soil are identical in character 

 with the same constituents in the original rock. When finely ground a certain 

 amount of these substances is dissolved directly in the soil solution, leaving the 

 remainder unchanged in composition. 



The method of examination proposed furnishe.- a means of rapidly determining 

 the constituent elements of the soil and their form of combination, as well as the 

 minerals from which they have heen derived, and is a valuable supplement to 

 chemical analysis. 



On the mineral constituents of cultivated soils, A. Delage and H. Lagatu 



' •[>!. 7.'./"/. Acad. Sci. [Paris], : , No. S6,pp. 1233-1235).— The results of 



microscopic examinations of 4 samples of soil taken at random are briefly reported, 



to show the complexity of the mineral constitution of soils in general and the value 



of this method of examination in determining the origin of soils. 



The constitution of cultivated soils, A. Delage and H. Lagatu {Ann. Ecole Nat. 

 Agr. Montpellier, o. ser., 4 [1005), No. S. }>p. 800-220). — A detailed account of investi- 

 gations noted above. 



Soil analysis as a guide to the rnanurial treatment of poor pastures, T. B. 

 Wood and R. A. Berry {Jour. Agr. Set, 1 (1905), No. 1, pp. 114-121) .—The results 

 of cooperative experiments on different kinds of soils, including analyses of the soils 

 and fertilizers used and a record of yields obtained, are summarized with reference 

 to their hearing on this subject. 



The general conclusions reached are "'that except in extreme cases the determina- 

 tion of the percentages of 'total' nitrogen, phosphoric acid, potash, and lime in a 

 soil do,- not give reliable indications as to the possibility of improving the pasture 

 by manuring. Determination of the percentage of phosphoric acid soluble in 1 per 

 cent citric-acid solution does generally give reliable indications as to the probable 

 success of phosphatic manuring, provided that for pasture soils the limit below which 

 'available' phosphoric acid may be considered as deficient is fixed as high as 0.02 

 per cent. 



"Potash manuring is suggested as likely to give distinct results if the soil contains 

 not more than 0.01 per cent of potash soluble in 1 per cent citric-acid solution. Lim- 



