130 Bulletin 394 



Percentage of 



Untreated germination 



seed after four 



days 



Lot I 28 



Lot 2 29 



Treated 

 seed 



Lot I 94 



Lot 2 95 



Lot 3 96 



These results are important in showing that it is not necessary to reserve 

 the acid treatment until just before the lot of seed is to be used, but that 

 seed so treated may be kept for months with no appreciable decrease 

 in the percentage of germination. Thus the process need not be left 

 to the farmer, in whose hands it might not be a success, but may be 

 carried out at the seed farm or by the dealer.^ 



THE POTS 



The pots in which the experiments were conducted were 9.5 inches 

 in diameter and 10 inches deep. The soil was sifted to remove the larger 

 pebbles, and a portion equivalent to about 25 pounds of moisture-free 

 fine soil was put into each pot. The soil was inoculated with the sweet- 

 clover organism by the pure-culture method. The cultures were obtained 

 from the Laboratory of Plant Physiology of the New York State College 

 of Agriculture. The pots were kept in the greenhouse and maintained 

 at a moisture content of 30 per cent. Quartz sand was spread over the 

 surface of the soil to lessen evaporation. 



SEASON OF 1914 



In accordance with the procedure just described, 36 pots were set up 

 in 19 14. In order to test the effect of lime on the growth of sweet clover, 

 the pots were divided into three series. In one series sufficient slaked 

 lime was added to .satisfy the lime requirement, while in another an 

 equivalent quantity of finely pulverized ground limestone was used. In 

 order to accurately meet the requirement the lime used was analyzed. 

 The third series received no lime. The seed was placed in the pots on 

 May 20. In sowing, the seedbed was rendered compact and the seed 



'Since this work was done, Professor H D Hughes, of the Iowa Agricultural Experiment Station, has 

 devised the Ames hulling and scarifying machine for the treatment of h.^rd seed. This machrne is 

 described in Farm and Firesidf, June 19. 1915. By treatment with it, germination is increased from SO 

 to 90 per cent. Many seed firms have installed the machine and have found it practical in every respect. 



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