224 EXPERIMENT STATION RECORD. 



acid pliosphate present. Even acid-free dried phosphate retained a certain 

 amount of potash. The higher the concentration of potash the more rapid the 

 retention. It was also found that ground phosphate roclc retained more or 

 less potash and that a part of the loss of potash observed in ordinary fertilizer 

 analysis occurs in the precipitate produced by ammonia and ammonia oxalate. 

 Tankage either showed practically no tendency to retain potash or in some 

 cases partially prevented the retention of potash. The retention of potash 

 was found to reach its maximum in stored goods. 



The author believes that these results "bear out the supposition previously 

 held that the retention of potash is not due in any marked degree to the forma- 

 tion of a chemical compound, but is nothing more nor less than happens to a 

 larger percentage of the potash when it comes in contact with the soil, as 

 shown by the work of Schreiner and Failyer" (E. S. R., 17, p. 1139). 



Sodium as a partial substitute for potassium, B. L. Hartwell and F. R. 

 Pember (Rhode Island Sfa. Rpt. 190S, pp. 2'i3-2So, pJ. 1). — In continuation of 

 the previous year's work with wheat (E. S. R., 20, p. 124), the water-culture 

 experiments were extended to include barley, oats, rye. and millet. The results 

 of both years' experiments are summarized in this article. 



" Experiments with millet, oats, barley, and rye seedlings showed, as with 

 wheat, that sodium was beneficial when used with a deficient amount of potas- 

 sium. Its effect with rye, however, was less than with the other cereals, direct 

 comparisons having been made with wheat and with barley seedlings. . . . 



" Increasing the amount of sodium to two and three times that which was 

 equivalent to the partially replaced potassium, the amount ordinarily used, 

 did not greatly change the extent of gain when compared with the growth 

 resulting from the deficient amount of potassium alone. 



" During a given time less potassium was absorbed by the seedlings when the 

 potassium was supplemented by sodium than when it was not. In other words, 

 sodium was a conserver of potassium. . . . 



" The experimental work seems to show that the beneficial effect of sodium 

 was not attributable to the increase of o.smotic pressure, to a. change of the 

 acidity or alkalinity of the nutrient solution, nor to overcoming the effect of 

 unfavorable quantitative relations of the nutrients in solution; although with- 

 out doubt sodium salts under certain circumstances act advantageously in these 

 ways. 



"Apparently certain of the uses of potassium with some plants at least, may 

 be performed by sodium; although there are certain principal functions of 

 potassium which can not be performed by any other element. If the amount 

 of potassium is insufficient for the performance of these exclusive functions, 

 probably maximum growth can not be secured with any amount of sodium 

 which may be added." 



Lime as a fertilizer, R. W. Thatcher {Washington Sta. Bui. 88, pp. 3-7). — 

 A brief statement is given of the beneficial effects of lime on soils and of the 

 forms of lime which may be used as a fertilizer. 



The decomposition of dolomite, N. Knight (Proc. Iowa Acad. ScL, 15 

 (1908), pp. 107, 108). — Analyses of more or less disintegrated dolomite showed 

 that about 10 per cent of the calcium carbonate had been removed and that the 

 magnesium carbonate had remained relatively stable. The layer immediately 

 above the disintegrated dolomite was a ferruginous clay which had probably 

 resulted from the dolomite by slow solution of the calcium and magnesium 

 carbonates. 



On sodium chlorid (cooking' salt) as a fertilizer for sugar beets, F. 

 Strohmee, H. Briem, and O, Fallada (Ostcn: Vngar. Ztschr, Zuckerindus. u. 



