166 Agricultural Section [pt ii 



from a less thoroughly cleaned sample. This test of absolute 

 weight is therefore an indication of quality. In the same way 

 the bushel weight indicates roughly the extent to which the chaff 

 and light seeds have been removed. The bushel weights of good 

 samples are given for each species in Table II, p. 175. 



Real Value. Provided a sample is free from noxious weed seeds 

 its "real value" or "cultural value" for practical purposes may be 

 said to depend upon the proportion of pure and germinating seed 

 it contains. Thus the "real value" 



Purity x Germination 



100 ' 



which gives the percentage of pure and germinating seed present. 



For example, a sample of Cock's-foot seed having a purity of 



90 per cent., and a germination capacity of 85 per cent, will — if 



the growth is normal — have a "real value" of — = 76-5 R.V. 



By employing such a method as this, samples which possess 

 different values for purity and germination may be compared 

 upon a common basis with one another. The "real value" figure 

 reveals the amount of useful seed present in a given bulk, which 

 is a very important point when making up seed mixtures. Thus 

 in the above example of Cock's-foot seed, each 100 pounds of the 

 bulk contains only 76-5 pounds of useful seed. 



Comparison of Seed Prices. 



The " real value " also shows what the relative cost of any sample 



should be. If we know that Cock's-foot seed with a " real value " of 



90 per cent, can be purchased at Is. 2d. per pound the cost of the 



14 x 76-5 



76-5 seed should not be more than — - — = ll-9d., say Is. 



90 J 



per pound. 



It should always be borne in mind that the actual price of 



seed is determined, not by the value of the plant to the farmer, 



but by (a) the cost of its production, and (b) cost of cleaning; 



and also by (c) the relation of supply and demand, i.e. the condition 



of the market. Since the prices fluctuate considerably no useful 



purpose would be served by quoting prices here. The latest price 



lists of merchants should be consulted. 



