8 BULLETIN 311, 17. S. DEPARTMENT OF AGRICULTURE. 



Valley Cotton Association. The types were also used in part as a 

 basis of business done with cotton merchants and mills in the East. 

 During the season of 1914 work was continued on these types, taking 

 into consideration the quality of the crop during both seasons, with 

 the idea of perfecting them so that the Department of Agriculture 

 could promulgate them later as standards. 



The amount of leaf, trash, foreign matter, and dead cotton, and 

 the color, are determining factors in establishing the grade. The bulk 

 of the crop of cotton up to the time of the first killing frost should 

 grade better than the basis grade, Choice, provided the cotton pickers 

 exercise a due amount of care in picking. The plant is alive, the 

 leaves firm, and the cotton is free of boll stain and can be picked free 

 of leaf. After a frost the plants are killed, the leaves dry and shrivel 

 up, breaking into small pieces which adhere to the cotton when picked 

 from the open boll. The frost having killed the plant, the boll is 

 forced open before all of the "fibers are mature. The action of the 

 frost on the sap in the cotton boll stains the lint, and also causes 

 flakes of cotton in the boll to perish; that is, the staple or fiber is 

 attacked by a fungus growth which discolors and weakens the fiber. 



In making up types the following points were taken into consid- 

 eration : 



(1) Amount of leaf, hulls, or foreign matter in the bale. 



(2) Color of the lint cotton. 



(3) Silkiness. 



(4) Amount of boll stain, dead cotton, etc. 



(5) Length of fiber. 



(6) Strength of fiber. 



(7) Uniformity of length. 



The Arizona grades, as worked out during this investigation and 

 study, with their equivalents in Egyptian cottons — corresponding to 

 the Official Cotton Standards of the United States in leaf only — are 

 as follows: 



Fancy. — Clear and clean, creamy color (allows about as much leaf 

 as Strict Good Middling, United States Government Standard), and 

 is equal to Extra Fine Sakellaridis Egyptian. 



Extra. — Clean, creamy or slight color (allows leaf about equal to 

 Good Middling, United States Official Standard) ; equivalent to Fine 

 Sakellaridis Egyptian. 



Choice. — Allows color after frost (allows leaf equal to Strict Mid- 

 dling, United States Official Standard); equivalent to Good Sakel- 

 laridis Egyptian. 



Standard. — (Leaf equal to Middling, United States Official Stand- 

 ard.) Equivalent to Fully Good Fair to Good Fair Sakellaridis 

 Egyptian. 



Medium. — (Leaf equal to Strict Low Middling, United States Official 

 Standard.) Equivalent to Strictly Good Fair Sakellaridis Egyptian. 



