AGRICULTURAL SEEDS, SELECTION AND TESTING 



261 



1. Whether the seeds belong to the species which it is desired to plant. 



2. Whether the sample is free from deliberate adulterations and from 

 noxious weed seeds and other noxious impurities. 



3. Whether the sample possesses a high percentage of viable seeds and 

 high vital energy, as shown by the rapidity with which germination 

 takes place. 



4. Whether they are of at least average volume- weight. 



In determining the first point, whether the seeds belong to the species 

 which it is desired to plant, a selected sample is spread out upon a piece 



v r 



FIG. 112. Mixture of weed seeds commonly found in low-grade alsike clover seed: 

 a, alsike clover; b, white clover; c, red clover; d, yellow trefoil; e, Canada thistle; /, 

 dock; g, sorrel; h, buckhorn; i, rat-tail plantain; k, lamb's quarters; I, shepherd's-purse; 

 m, mayweed; , scentless camomile; i, white campion; p, night-flowering catch-fly; 

 q, oxeye daisy; r, small-fruited false flax; s, cinquefoil; /, two.kindsof peppergrass; u, 

 catnip; v, timothy; x, chickweed; y, Canada bluegrass; z, clover dodder; i, mouse-ear 

 chickweed; 2, knot-grass; 3, tumbling amaranth; 4, rough amaranth; 5, heal-all; 6, 

 lady's-thumb. (Enlarged.) (After Hillman, F. H.: The Adulteration of Forage-Plant 

 Seeds. Farmers' Bulletin 382, 1909, p. 10.) 



of white paper and the seeds gone over one by one (Fig. 112). All foreign 

 seeds, if any are present, are removed and later weighed. The percentage 

 obtained by weighing will give the purity of the sample. In purchasing 

 seeds in the market, we cannot expect to obtain the highest possible qual- 

 ity, or 100 per cent, of real worth. One hundred per cent, is the ideal 

 standard of measurement and at best we can only hope to approximate it. 

 Agricultural seeds, 99 per cent, pure, may be considered to be very high 



