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2. SOAKING IN WATER 



Grains which had been immersed in kerosene were soaked in 

 water for from one to forty-ei^ht hours and then placed, together with 

 a check, under the usual conditions for germination. It was found 

 that soaking in running water for periods of from one to eight hours 

 was not injurious and in a few instances seemed slightly beneficial. 

 When soaked for longer periods a decided reduction in the per cent. 

 of germination was manifested. Abnormalities in the later growth of 

 the seedlings from grains immersed in kerosene and subsequently 

 soaked in water for the shorter periods were more frequent than from 

 unsoaked grains. On the whole it seemed clear that the smaller the 

 amount of water present in the grain at the time of planting and con- 

 sequently the more slowly the growth processes were initiated the less 

 serious were the effects of the kerosene. 



3. MOISTURE CONTENT OF THE SOIE 



The moisture content of the soil was varied from the minimum 

 amount necessary for germination to complete saturation. The re- 

 sults were so diverse that it was decided to make three sets of tests, 

 identical in every way except the water content of the soil. The first 

 contained approximately the minimum amount in which germination 

 would take place readily; the second, the maximum amount in which 

 germination and normal growth of control grains could be secured; 

 and the third, an amount which represented an approximate mean to 

 the other two. Different soils vary so widely in their power to hold 

 water that the percentages of saturation used to secure the conditions 

 indicated above must necessarily be determined by experiment and can 

 only be made to apply to the particular soil used. 



4. CULTURE MEDIA 



The grains were germinated in the ordinary germinating pans, in 

 yellow clay, sand, sawdust, black loam, and in various mixtures of 

 sand and- sawdust and of sand and black loam. Of these the sawdust 

 was the only one which showed any harmful effects. The use of the 

 germinating pan was early discontinued because of the necessity of 

 making observations on the growth for some time following germina- 

 tion. A mixture of black loam and sand yielded as good results as 

 any other, and this was selected because of its adaptability for vary- 

 ing and maintainim: the moisture content. 



