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with the character of the season, but its chief features are, 

 first, a weakening of the vitality of the plant from any cause 

 during mid-summer ; and second, the rapid development on 

 the weakened leaves of one or more species of fungi, causing 

 dead blackened spots and ultimately the premature falling of 

 the leaf. Fortunately the species of fungi connected with 

 this disease do not have the power of attacking cotton foliage 

 that is in a strong, actively growing condition. The lessened 

 vitality that renders the leaves subject to attack may be 

 caused by improper soil conditions, by prolonged drought, by 

 too much rain, or probably by any other cause that tends to 

 suddenly check the growth of the plant. If it were possible 

 to keep cotton actively growing without any set backs 

 throughout the entire season, there would be little or no lia- 

 bility to loss from rust. 



" Obviously, then, our problem in seeking are medy for 

 this disease is to learn to so treat our cotton fields as to main- 

 tain as nearly as possible this desired condition of continuous, 

 uninterrupted growth. 



"Owing to the great diversity of our soils and the varying 

 character of the seasons, it is difiicult or impossible to devise 

 any one plan of treatment that would prove successful in all 

 cases. The Experiment Station, therefore, earnestly desires 

 your CO operation in studying this question under the condi- 

 tions existing in your own Jocality. 



" Experiments conducted by Dr. Atkinson and others show 

 that in some cases applications of kainit have a remarkable 

 effect in preventing rust. My own observations during the 

 past two years seem to show, at least for our thin hill lands, 

 that those soils well supplied with vegetable matter, such as, 

 new ground, old fence rows, and lots near stables have suffered 

 much less than old fields, where the vegetable matter or humus 

 has been exhausted by constant cropping. 



" Since this question is one of such general interest will you 

 aid us by answering the following questions, and by carrying 

 out the simple experiment suggested below, and reporting its 



results to me? 



"1. Have you suffered from the rust either in 1896 or 189/ .'' 



If so, what per cent, of your crop do you estimate as lost? 



" 2. What is the character of your soil ? In what kind of 

 locations has the rust been worse with you ? 



"3. Have you used kainit in your fertilizer? Ifso,inwhat 



quantity and what effect, if any,"have you observed from it as 



to rust? 



"4. Is new or old land most subject to rust in your 



locality ? 



