Diseases and Injuries 



very rapidly among the cuttings, as soon as the roots are formed in the 

 cutting bench. 



Many remedies have been advised and elaborately described ; but after a 

 thorough trial of most everything that has been put forward as a cure for 

 Rust, I have come to the conclusion that a plant once thoroughly infected 

 cannot be absolutely freed from the disease until it has run a certain course 

 through the tissue of the plant, and exhausted itself. 



In an article read before the American Carnation Society, at its annual 

 meeting in 1893, the author recommended spraying the plants with Bordeaux 

 Mixture, or the ammoniacal solution of carbonate of copper. At that time, 

 when Rust first appeared, I had apparently cleared it from the plants, by 

 spraying with Bordeaux Mixture ; but subsequent tests, under different con- 

 ditions, prove the spraying to have but little effect, and, at the present time, 

 I am satisfied that these plants would have recovered from the disease in a 

 natural manner, had they been left unsprayed until the disease had run its 

 course. 



Recent experiments by the United States Department of Agriculture 

 seem to demonstrate that, where a fungus infects a certain family of plants, 

 the disease may be wholly got rid of, by allowing it to exhaust itself. It 

 will generally be found that, when the cycle of fungoid growth is complete, 

 there will remain a certain percentage of unaffected plants. By propagating 

 from these, a strain will be produced which is capable of resisting, or over- 

 coming, the attacks of the disease. I am inclined to the opinion, that more 

 benefit will be derived from pursuing this course in propagating carnation 

 stocks, than by any treatment in the way of spraying with different mix- 

 tures that has yet come under my observation. 



Of late years, we have dispensed entirely with spraying the plants for 

 the purpose of curing them from attacks of Carnation Rust. The disease 

 is located within the tissue of the plant, and the brownish powder given off is 

 but the fruiting spores ; so that while we may reach these spores by the 

 different sprays recommended, the fungus itself retains its vitality, and 

 continues to give off these fruiting spores until it is exhausted. 



I have never yet seen a healthy carnation plant killed when attacked by 

 the Carnation Rust, although I have frequently seen the strongest and most 

 vigorous plants affected by the disease to such an extent that for a time 

 growth was largely arrested. Nevertheless, after the disease had fruited for 

 a certain period, the plants seemed to recover from the attack, and grew 

 as vigorously as before. 



So far as spraying has been tried, I believe that the salt solution, 



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