464 



soil? (2) Can com obtain its nitro;,'f'Ti iVuni that present in ins«»ln1)le 

 orjranic; coinpounds, as in decayed roots, etc., and what is the relative 

 vahie of nitrogen in tliis state of combination compared witli that 

 present in the form of nitrates?" 



A review is jjiven of " the existinjr theories eoncernin;; the assimihition 

 of nitrogen by ]»lants," and of observations on the etiects of ditierent 

 nitrogenous fertilizers on corn. 



The exi)eriments were made in galvanized iron cylinders 11 inclu-s 

 in diameter and 20 inches deep. A layer of gas coke about 5i inches 

 deep was phued in the ])ottoni, and above this sand. Tliere wen* fonr 

 series of experiments with twelve pots in each series. All received 

 hydrous donbh* silicate of potash and aluminum, precipitat<Ml cahium 

 phospliate, gypsum, and ferrous snlphate. 



T«» tin- first row of pots no otluT iMldilion was made. 



Thj" 8f<-oinl n-reivril two additions of aqueoiiH soil •■xtraot, applied to tho roots 

 of th<' voiiii^ jdant. This aqueous fxtrart rontained le«s tlian 0.01 por i-ont of 

 nitrojjeii, so tliat the small amount of this in<;ri'di«-iit added wa^ of no practical 

 importanc (^ 



The third row re<«ived its nitro^jen in th<- form of Mack peat, carefully extract«'d 

 with water till the latter ceased to take up aiijireciable <|uantitie8 of nitrogen. The 

 residual material, carefully dried and pulverized, contained 0.01 per cent of phos- 

 phoric acid, O.L'."> jier cent of potash, K.T.") jter <ciit of nitrogen. 



To tho foiirtli row nitro-ien waw ap]died chiefly as sodium nitrate, beiii;: intro- 

 duced into the cli;inucls of the jMtts whence it would reach the jdants hy ditftisitui 

 throu;;h the cajvillary jMues of the soil. * ' * A small i|uantity of ammonium 

 Buli)h:it<' iu solution was introdiicd aliont tin- s.ed .-,0 as to In- ready for tlie vouuk 



plant. • • • 



[The results of the expi-rinniit are tahulated. and illustrated l>y four jdates.) 



In no case were the conditions such as to secure a tull normal developnunt id" the 



]dant. 



The results show that iu all the rows the cr«>p containe«l Krt'f***''" amounts of 

 uitro-'en than were sui»|>lied iu the seed, Imt that under the conditions ahove 

 mi'iitioiied the presen<-e of microorK^niisms obtaincil from fertile soil did not einilde 

 the jdauts to assimilate more nitrogen than they assinulated wln-re tlrv extract was 



not used. 



The imrcase in quantity ol>servid may l>e attril-utcd to the sli;;htly availahle 

 nitroK«'n of the sand, so that these ex])crimcnts yive us no dctinite kn«)wled;jc that 

 maize is able to take up any free nitrogen from the atmosphere through the soil. 



It is also found that under the above ccuiditions of growth ni.ii/e is unalde to 

 utilize peat nitro;jjen as well as it can that of nitrates. Altout one twentieth of the 

 nitro<;en oftered as peat and about one third of that ofl'er.-d as nitrat«>s was taken up 

 in the maize cnq). The total crop where nitrates wvw used was nearly nineteen 

 times ;;reater than where no nitrogen was applieil. With peat nitro;;en the increase 

 was not rpiite fourfold. 



Mkti:(»kology, W. Freak, IMi. I), ipp. l'OC^l'2;? and 2.57-27S).— The 

 work in ISSO was along the same lines as tliat reporte<l in tlie .Vnniial 

 lleport of the .station for 1S88 (see Experiment Station litdh'tin No. 2, 

 part II, p. l-iO). and included observations on atmosjiheric ]»henom«'na, 

 soil temperatures, amount of sunshiiu', ami soil moisture, ^bmthly 

 .summaries of the nu>teorological ob.servations and weekly croi) rei)«ti ts 

 are given in the body of the report and the detailed record of daily 

 observations in an appendix. 



