2 Bouyoucos, Transpiration of Wheat Seedlings ae Afiected etc. 



Review of Literature. 



The literature bearing directly upon this part of the inrestigation is ra 

 limited, considering the importance of the subject. Of the nfv^'' '™P 

 works reported on the subject may be mentioned the following: ^v 



Burgerstein*) in his investigation upon the transpiration of ^IlI^ 

 studied also the efifect of different densities of Solutions of Ca (N03)a , KNo^ 

 KjHPO«, K2CO3, NH« NO3, (MH^)^ SO4, and other chemicals. He found 

 that transpiration increased with the increase in density of all these single salts 

 up to a certain point, above which it began to decrease. 



Schroeder^) found that the amount of water transpired, per unit of 

 dry matter produced increased with the concentration of the nutritive material 

 present, up to a certain density, beyond which it feil. 



Sorauer^) grew plants for eiglit weeks in a nutrient Solution of different 

 concentrations. He found that the relative transpiration decreased with the 

 increase in concentration. 



Heinrich*) studied the amount of water transpired by oats in a complete 

 nutrient Solution of different strengths. He found that transpiration decreased 

 per unit of dry matter, with the increase in concentration. 



Maercker^) grew white mustard in an artificial soil, contained in zinc 

 pots. He added to the soil different amounts of moisture and various quantities 

 of Kainit and Carnallite, and studied the effect of these salts upon the amount 

 of water required to produce a given quantity of dry substance. He failed to 

 seal the pots to prevent the direct evaporation from the surface of the soil, but 

 the results he obtained go to indicate that the application of the potash salts 

 produced a distinct economy in the absorption of water, and this was more 

 marked in the lower than in the higher moisture Contents. 



Kiesselbach 8) grew corn for two and a half months in pure river 

 sand watered with a complete nutrient Solution. His results show that the 

 amount of water transpired per gram of dry matter, tends to increase with the 

 decrease in density. 



General Methods of Investigation. 



In the present work the effect of the different densities of 

 Solution upon the transpiration of plants, was studied in water, 

 sand and soil cultures, at the same time and under the same con- 

 ditions. 



The water cultures were prepared and conducted according 

 to the methods recoramended by the Bureau of Solls ''), with a few 

 modifications. 



») Sitzungsber. Akad. Wiss. Wien. Math.-Nat. Gl. Bd. 83. 1876. p. 191. 



2) Anw. Inst. Agr. Moscow. 2. 1896. p. 188—226. 



3) Allgem. Brauer- u. Hopfenzeitg. 23. 1882. p. 15—19. 

 *) 2. Ber. Landw. Vers.-Stat. Rostock. 1894. p. 170-174. 

 «) Arbeit. Landw. Ges. H. 20. 1896. 



«) Nebraska Agr. Expt. Sta. 23 rd. Ann. Rept. 1910. p. 138. 

 '} Bull. 23, Bureau of Solls, U. S. Dept. of Agr. 1904. 



