4 BTJLLETIISr 60, U. S. DEPARTMENT OF AGRICULTURE. 



considered inevitable. The deterioration of cotton varieties is often 

 tiiought of in a similar way, as something" that is sure to occur in a 

 few 5'-ears. But such deterioration can be avoided just as definitely 

 as wounds can be protected from infection. 



The most frequent source of the infection that causes a variety 

 of cotton to degenerate is mixture of seed or crossing with other 

 varieties. The planting of different varieties close together and the 

 exchange of seed at the gin are the usual causes of contamination. 

 The present system of public gins might be described as an unconscious 

 conspiracy to destroy the purity of varieties and does miUions of 

 dollars' worth of unrecognized damage in this way every year. The 

 machinery of the gin is arranged to hold a bushel or more of the seed 

 of each customer and to mix it into the seed of the next farmer in the 

 hne. No farmer can keep his variety pure who allows a public gin 

 to handle his seed in the usual way. To keep his variety pure, a 

 farmer must either have his own gin or he must find a public gin 

 where he is allowed to clean the machinery and thus keep his seed 

 from being mixed. Very few farmers think of taking such precau- 

 tions. They prefer to beheve, as a correspondent recently assm^ed us, 

 that '"what httle gets in at the gin wi\l not do any harm." 



^'^ hen mixture A\dth other kinds of cotton is avoided, it is still 

 possible for a variety -to degenerate, in the sense of losing its uni- 

 formity, unless care be taken to recognize and remove the "sports" 

 or aberrant plants that continue to appear in even the most carefully 

 selected stocks. To rogue out these degenerate plants is as necessary 

 as to prevent mixing \\ith other varieties. The degenerate individ- 

 uals are hke so man}^ different varieties, for the characters of many 

 of them "come true" when the seeds of such plants are saved and 

 planted separately. It is only by observing these two precautions 

 of avoiding admixture and roguing out the "freaks" or "sports" as 

 they appear that varieties are kept from deterioration and made to 

 serve the purposes of production for many years. 



After a discovery hke antiseptic surgery has been made it seems 

 altogether unreasonable that people should disregard it, at the risk 

 of pain or even death. But it is the lesson of history that reforms 

 come slowly, and the improvement of the cotton industry is hkely to 

 follow this rule. It is only when we undertake to avoid infection or 

 contamination that we learn how difficult it is to do so. Even after 

 the farmer understands the importance of maintaining a pure stock 

 of seed there are many ways to bring in contamination, and some of 

 the most intelligent and efficient farmers often make fatal mistakes 

 in their first efforts to maintain a pure stock of seed. The most 

 disappointing cases are those where some accident or error occurs 

 after most of the precautions have been taken. It is not until the 

 farmer learns to think, as it were, in terms of pure seed that he is 

 able to guard himself all along the line of possible errors. 



