3S PASTURES AND PASTURE PLANTS CHAF 



loo. For instance, a guarantee of 98 per cent, of purity and 90 per cent, of 



germination with Red clover signifies that 98 of every 100 seeds are pure or 



true, and that 90 of them grow. 



Real Values. — Since impure seeds and those that have lost their power 



of germination by injury or age are useless, the percentage of pure and 



germinating seeds of any sample indicates its real value. This is easily 



determined by multiplying the percentages of purity and germination together, 



and dividing the product by 100. Thus, the real value of any seed 



Purity X Germination , , , ^ , , . , • , ,• 



^ , that of the Red clover mentioned m the precedmg 



paragraph being = 88-2 per cent, or, approximately, 88 per cent, of 



pure and germinating seed. The real value being known, it is a simple 

 matter to ascertain the actual weight of useful seed in any parcel. Supposing 

 a bag of Red clover to contain 10 lbs. having 88 per cent, real value, then 



QQ QQ 



only of the weiffht of the whole is useful, that is of 10 lbs. 



100 ■' ° 100 



88 >< 1° o „ •,, 

 = 8-8 lbs. 



1 00 



The real value also shows the comparative worth of different samples, 

 since i lb. possessing 88 per cent, of pure and germinating seed is equal in 

 value to 2 lbs. with 44 per cent., or to 4 lbs. with 22 per cent, only, because 

 I X 88 = 2 X 44 = 4 X 22 = 88. 



Percentage-lb. -Value. — Stebler has suggested that the weight of any 

 quantity of seed multiplied by its real value be called its percentage-lb. -value ; 

 and this appears to be the most simple and satisfactory method of expressing 

 the exact worth of the whole parcel ; and it also admits of the relative worth 

 of different weights of seeds of varying qualities being readily compared, as 

 will be seen from the following instances : — 



Name of variety. I Weight in lbs. Percent.iseof real value. ib.-value. 



Red clover 1 20 1 So 



Do. 40 I 20 



Do. ' 80 10 



i,6co 

 800 

 800 



The percentage-lb.-values of the 20, 40, and 80 lb. bags are respectively 

 1,600, 800, and 800, so that the 20 lbs. is equal in value to the united worth 

 of the 40 and 80 lbs., since 1,600 = 800 -f- 800. 



Quantity per Acre. — Since, then, 1 lb. of Red clover with 88 per cent, 

 of pure and germinating seeds is worth 2 lbs. having 44 per cent, only, it is 

 clear that the weight of any variety required to sow an acre depends entirely 

 on the real value of the actual seed to be sown ; and it is equally evident that 

 calculations can only be safely based upon the amounts of perfectly pure and 

 germinating seeds (100 per cent, real value) that experience proves are needed 

 per acre for pure sowing. Such data have been compiled by many agricul- 

 tural writers, but the following tabulated statements, the second of which is 

 partially after Stebler, may be regarded as reliable. 



