<^ I LIBRARY 



IV0V2 mi 



l^M^ INTERMOUNTAIN FOREST AND RANGE EXPERIMENT STATION 



<j^:iO- Ogden, Utah 



, Reed W« Bailey, Director 



Research Paper No. 5 September 19^5 



QOQD SEES FOR RANGE RESEEDING 

 By A.* C. Hull, JTr*, Assistant Forest Ecologlst 

 and C* Kenneth Fearse, Conservationist. 



Basis of Seed Quality 



Good quality grass seed is essential to successful artificial rsseed- 

 ing of range lands. Quality of seed depends primarily upon genuine- 

 ness, purity, and degree of germination. Genuineness refers to freedom 

 from adulteration with cheaper seed. Fortunately, range grass seed is 

 seldom adulterated, although errors in labeling, due to unfamiliarity 

 of the dealers with the species, may occur. Seed purity is the percent- 

 age by weight of uninjured pure seed of the species listed on the label. 

 In a purity analysis seed is separated into pure seed, other crop seed, 

 weed seed, and inert matter which includes such things as broken seed, 

 chaff, and dirt. Germination is the percentage of the pure seed that, 

 under normal environment, is capable of developing into normal plants. 



Under ordinary conditions the buyer is not interested in either the 

 purity or germination alone but in the amount of seed that will grovj. 

 The pure, live seed content, obtained by multiplying the germination 

 by the purity, represents the real value of the seed. Thus seed with 

 a germination of 95 percent and a purity of 96 percent contains 91»2 

 percent pure, live seed; on the other hand seed with a gemination of 

 57 percent and a purity of 80 percent contains 45.6 percent pure, live 

 seed or but half as much as the first lot. If there are no other differ- 

 ences the first lot would be worth twice as much as the second lot and 

 would yield as many plants per square foot if seeded at half the rate. 



By dividing the percentage of pure, live seed into the cost per pound '* 

 the actual cost of a pound of pure, live seed can be obtained. If a 

 price of 15 cents per pound is asked for the first lot of seed in the 

 above example, the actual cost of a pound of pure live seed would be 

 15 divided by 91,2 or approximately 16^ cents. If 10 cents per povuid 

 is asked for the second lot the actual price of a poimd of pure, live 

 seed would be approximately 22 cents. When the germination and the 

 purity are known, the buyer thus has a guide for determining the real 

 value of the seed. 



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