22 



CIRCULAR NO. 122, BUREAU OF PLANT INDUSTRY. 



average difference between the yields of unfertilized and fertilized 

 rows was insignificant. Tlie indications are that on rich soil, such 

 as was used in this experiment, commercial fertilizers are of little or 

 no value. 



STRAAVBERRIES. 



In April, 1912, 25 plants each of 20 varieties of strawberries were 

 ]:)lanted on the farms of W. J. Ferguson, P'allon district ; W. Van- 

 voorhis, Stillwater district ; and W. W. Cogswell, Fernley district. 

 As strawberries do not produce a crop until the second year, a report 

 can not be made at the present time on the relative desirability of 

 these varieties. 



ALKALI AND GROUND- WATER STUDIES. 



Since the establishment of the experiment farm studies have been 

 made to determine the causes of the poor growth made by plants on 

 much of the land, not only on the experiment farm but on numerous 

 other farms on the project. Some very definite results have been ob- 

 tained and are being i^repared for publication. 



It has been found that sodium carbonate (" black alkali "), sodium 

 bicarbonate, and sodium chlorid are the alkali salts chiefly affecting 

 the growth of plants. These salts are found in widely varying quan- 

 tities on different parts of the project, and the proportions in which 

 they are associated are very irregular. Table V states, in percentages, 

 the quantities of sodium carbonate, sodium bicarbonate, sodium 

 chlorid, and other salts found in field S on March 16, 1912, where 

 alfalfa was doing well and also where its growth was not good. This 

 table gives a general idea of the nature and quantities of the alkali 

 salts found on much of the land on the project, but, as before stated, 

 there are Avide variations in this feature. 



Table V. — I'crcciilitiic of all.dii sdlts tlcicniiiiicd <m Mmcli Id. I'.il.l. on aii nlfiilfa 

 plat ill field N, I'nivkcc-Curnoii f-lrtxiiiiiciit I'diin. 



Before successful crop production can be accomplished on lands 

 containing harmful quantities of these salts, methods for i-educing 

 the salt content of the soil nuist be perfected and put into practice. 



[Cir. 121'] 



