SOILS. — FERTILIZERS. 125 



tlio availability of the nitrogen of this guano, a largo part of wbicli is in the 

 form of chitin, are reported. The I'esults show that the undecomposed chitin 

 is not a readily available soin-ce of nitrogen. 



Concentration of sugar beet vinasse for fertilizer, M. I*. Kestner (Bet- 

 jcravc, 1906, A-o. J/ll, PP. 403-406; aJ)S. in Client. Abs., 1 (1907), No. 9, pp. 1159, 

 1160). — Instead of using the vinasse for recoveiy of potash as usual, it is pro- 

 posed to mix the dried vinasse with peat or other absorbent material and thus 

 l)repare a fertilizer containing nitrogen as well as potash. The increased cost 

 of preparation is said to be offset by the higher value of the product. 



Continued test of nine phosphates with different plants, H. J. Wheeler 

 and G. E. Adams (Rhode Ii^land ^'?ta. Bui. 118, pp. 55-86). — A previous bulletin 

 reported the results of these tests up to and including 1901 (E. S. R., 18, p. 019). 

 This bulletin reports a continuation of the tests with soy beans in 1902 ; with 

 Alaska peas, beans, squashes, potatoes, ruta-bagas, turnips, mangel-wurzels, 

 barley, millet, oats, cabbage, tomatoes, lettuce, spinach, and crimson clover in 

 190;? : and with oats in 1904 ; also with redtop following the miscellaneous 

 crops grown in 1903. 



The experiments embraced tests of the relative efficiency of the same 9 

 phosphates (dissolved boneblack, dissolved bone, acid phosphate, fine ground 

 bone, basic slag meal, floats, raw and roasted redondite, and double superphos- 

 phate) used in previous trials on the same soil, limed and unlimed. The appli- 

 cations of phosphates were equalized for the first time in 1902, sufficient amounts 

 of each phosphate being added in that year to bring the I'ate of application for 

 the entire period, 1894-1904, up to 67.12 lbs. of phosphoric acid per acre per 

 annum. 



As in previous trials liming greatly increased the efficiency of roasted redondite 

 but was without influence on the raw redondite, as " in several cases in the 

 limed series the results were better without than with the raw redondite." 



'• In the unlimed series neither the raw nor roasted redondite proved to be 

 of much practical value when used in connection with most of the varieties of 

 plants. The crimson clover, potato, and especially the Japanese millet, oat, and 

 golden millet, furnished, however, some notable exceptions. 



" Floats gave very good results with the soy bean, peas, crimson clover, 

 mangel-wurzel (on limed land), barley (on limed land), potato (on unlimed 

 land), Japanese millet, oat, and golden millet, but they proved highly inefficient 

 especially for the Hubbard squash, ruta-baga, crook-neck squash, flat turnip, 

 cabl)age, mangel-wurzel (on the acid unlimed land), tomato, lettuce. New 

 Zealand si)inach, and red valentine bean. 



"As a rule in the unlimed series, especially in the case of plants which are 

 subject to injury by acid soils, double superphosjihate failed to give good results. 

 The same inferior action, in a less degree, was observed in the case of certain 

 plants both with dissolved boneblack and acid phosphate. 



"In one or two cases the results with acid phosphate were quite poor even 

 in the limed series, but whether this was incidental or due to the presence of 

 some compound peculiar to this substance, which is particularly toxic to certain 

 I)lants, remains to be determined. . . . 



" Basic slag meal and fine ground bone proved to be excellent phosphatic 

 mamn-es for acid soil, the former being immediately efficient and the latter 

 becoming so after remaining in the soil for 2 or 3 years or long enough for 

 extended decomposition to result. 



" Thes(» results ought to show that attention nuist be paid to the kind of crop, 

 the kind of phosphate, and the kind of soil, if one will make sure that the phos- 

 phoric acid shall pay proper returns for the money employed in its purchase." 



