For purity: Allowing "a" to represent the component being con- 

 sidered and "b" the difference between that percentage and 100, accord- 

 ing to the following formula : 



( a X b ) 



Pure seed tolerance=0.6 + ( 0.2 X ) 



( 100) 



a sample of timothy guaranteed 99.20 % could test as low as 98.40 % and 

 be "satisfactory." 



For germination : The following tolerances are applicable : 



Mean : Tolerance 



96 or over 5 



90 or over but less than 96 6 



80 or over but less than 90 7 



70 or over but less than 80 8 



60 or over but less than 70 9 



Less than 60 10 



Therefore, a sample of seed guaranteed 85 % for germination may be as 

 low as 77% and be "satisfactory." 



For weed seeds : The law requires in the labeling of agricultural 

 seed (1) that the percentage of all weed seeds present shall be shown on 

 the tag (2) that no primary noxious weed seeds shall be present in the 

 sample, and (3) that, if present, the names of the kinds of secondary 

 noxious weed seed and the rate of occurrence of each shall be stated: 

 (A) Per ounce in Agrostis spp., Poa spp., Rhodes grass, Bermuda grass, 

 timothy, orchard grass fescues, alsike and white clover, reed canary 

 grass, Dallis grass, ryegrass, foxtail millet, crimson clover, Brassica spp., 

 flax, Agropyron, spp., and other agricultural seeds of similar size and 

 weight, or mixtures within this group, and 



(B) Per pound in proso, Sudan grass, wheat, oats, rye, barley, 

 buckwheat, sorghums, vetches, and other agricultural seeds of a size and 

 weight similar to or greater than those within this group or any mix- 

 tures within this group. 



Certain tolerances are allowed, however, to provide for variation 

 and unavoidable errors, but only within very narrow limits and for which 

 there is always a standard formula for computation. Examples: (1) 

 Timothy guaranteed only 2 per cent weed seeds will not be condemned 

 if it has a 2.59 per cent. (2) No primary noxious weed seeds are allowed, 

 but the presence of two such seeds in 50 grams of timothy would not be 

 considered a violation. (3) Similarly, some slight variation from the 

 minimum requirement for labeling secondary noxious weed seeds will be 

 passed as satisfactory. 



Free Testing 



The Seed Testing Laboratory will allow two free tests, in a given 

 year, to any resident company or person of New Hampshire, but such 

 seeds must be received in the laboratory during the months of October, 

 November, December and January. This number of samples, not in- 

 cluding mixtures, may be analyzed either for purity or for germination, 

 or one sample for both purity and germination, free of charge. A given 



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