The Effect of Borax in Fertilizers. 107 



cc. of water respectively per pot daily. All of the water was 

 applied in the saucers, thus making the water current always 

 upward through the soil in the pot. 



Temperature. The temperature control was set at about 

 70 degrees F. during the day and from 50 degrees to 55 degrees 

 F. during the night. During the night of December 15 on 

 account of the failure of the University heating plant to fur- 

 nish sufficient steam the temperature fell to the danger limit 

 and some of the plants nearer the walls of the house were frozen. 

 This seriously interfered with certain features of the work and 

 made it impossible to make some desired photographic records r 

 but it did not materially affect the final results and conclusions. 



Records. While changes in the appearance of individual 

 plants were noted as soon as they appeared, detailed records of 

 the growth and appearance of each plant were made weekly. At 

 the close of the experiment all plants were removed from the 

 pots and the root systems separated from the soil as carefully 

 as possible and examined for injury. 



RESULTS OBTAINED FROM GREENHOUSE EXPERIMENTS WITH 



POTATOES. 



Except for some mosaic the unfertilized check plants re- 

 mained perfectly healthy till they were removed from the pots 



3 months after planting. The plants in the pots containing the 

 borax-free fertilizer No. 5409 were entirely free from any evi- 

 dence of fertilizer injury or disease. This entire lot was in- 

 cluded in the few plants which were badly injured by frost. 

 However, all of the other plants which developed borax injury 

 had shown it, in marked degree, some time previously. Of the 



4 pots fertilized with No. 5409 one was about 9 inches high and 

 the other 3 about 15 inches high when killed by frost on Decem- 

 ber 15. Unfortunately no photographs had been taken to show 

 their appearance at that date. All that can be said is that at 

 this time the health and vigor of these 4 plants showed a marked 

 contrast to the other 40 in the experiment, including the un- 

 fertilized checks. 



No plants which received fertilizer containing borax es- 

 caped injury in some form or other. In general the amount of 

 injury varied with the amount of borax present in the fertilizer 



