PREPARING SEED BEFORE SOWING. 201 



ter, for practical experiments show that when the 

 ambient temperature remains at 48 degrees F., about 

 twenty days are needed for seed to appear above 

 ground. While, on the other hand, at 63 degrees F., 

 the rows are distinctly visible in about three days. 

 Consequently, on general principles, it may be admit- 

 ted that the rapidity of germination is in direct ratio to 

 the ambient temperature. 



It is claimed that in preparing beet seed, it is pos- 

 sible to give a certain number of degrees of heat in 

 advance, and in connection with this matter, there 

 would be a gain in the number of days for sprouting.* 

 For soils in general, the requisite time for germination 

 may be considered inversely proportional to its tem- 

 perature. The cold has an important effect, and an 

 early frost will kill the germs of a large number of 

 seeds planted; hence, the desirability of being very lib- 

 eral with the quantity of seed used. It is admitted that 

 germination ceases at about 3 degrees C, or at a max- 

 imum, 30 degrees C. The heating and cooling of soils 

 during the spring of the year has an important influ- 

 ence not to be overlooked. The warmth during the 

 day and the cooling at night are said to have an accel- 

 erating effect on germination. It must be thoroughly 

 understood that the action of low temperature on beet 

 seed is very slight, providing germination has not com- 

 menced, and is very destructive after the first signs of 

 life have manifested themselves. The best authorities 

 admit that seeds germinate under the best conditions 



•If seeds, for example, remain two days in a liquid at 22.5='C., the 

 total heat thus ^i /en would be 45° C. ; the remaining inimber of de- 

 crees to be furnished then becomes 130° C. — (m in us) 45° C. —85° C. If during 

 draining of seed the ambient temperature is 15° C. the heat left to be fur- 

 nished would be 70° C. If the temperature of the soil is 10° C. 

 and remain constant, then germination would take place 70 



"To 

 or seven days. If there had been no preparation, the number of days 

 for germination would have been 130 



IQ— 13 days. The preparing of seed 

 lias thus been a gain of six days. 



