THE SECRETARY'S PORTFOLIO. 345 



from the flowers, by contact of the roots, and by pruning a healthy tree with a 

 knife used on a diseased one. It sometimes spreads more rapidly and generally 

 over an orchard in oLhcr unknown ways, and we have known it to attack trees 

 miles away from any affected with the disease. In any reported observations, 

 it is important to know this disease distinctly, as mistakes are sometimes niade 

 by supposing other maladies to be the yellows. The lirst clear indication is the 

 •premature ripening of the fruit, with purple discolorations of the flesh, and 

 deficient flavor. These are followed, usually the next year, by numerous wiry 

 shoots near the center of the head, a general sickly and yellow appearance, and 

 death. No remedy has been found or generally adopted, but quite recently 

 some experiments have been made that point to a copious application of potash 

 or some of its compounds, as promising a prevention if not a positive cure — 

 muriate of potash having been used for this purpose. The theory assigned is 

 that the vessels of the affected tree are surcharged with starch, which the pot- 

 ash dissolves and dissipates ; but further experiments are required. 



The same journal remarks at another time an article which has appeared 

 in some of our exchanges, credited to the American Naturalist, repeating the 

 opinion that a thin and poor soil contributes mainly to the prevalence of the 

 yellows in peach trees. This is doubtless true in some instances, but, as in 

 other cases, and with other theories of tree diseases, facts frequently come in 

 and seriouslv interfere. We have seen many trees affected and destroyed by the 

 yellows within the past half century, some on poor soil and many on strong 

 and rich soil, and one of the Worst cases of this disease which we have seen was 

 in a beautiful thirty-acre peach orchard, the soil of which was naturally strong 

 and rich, and was highly cultivated. We shall have to modify some of our 

 theories. 



* * * ^-. >!c * * * * * * * * * 



At the meeting of the Western New York Horticultural Society, it seems 

 a short session was devoted to the yellows. Dr. E. L. Sturtevant spoke briefly 

 on the diseases of vegetable substances, and said that a free use of muriate of 

 potash had been found an efficient remedy for the yellows in the peach ; others 

 had tried it with success. Potash was the needed substance, and the muriate 

 was used because it was a cheap commercial compound. It must be applied in 

 excess of the demands as plant food, the precise amount not yet determined, 

 probably not over three or four pounds to the tree. Mr. Harrison, of Ohio, 

 said that fresh wood ashes had been used successfully for the yellows. E. A. 

 Bronson, of Geneva, mentioned instances where fresh lime heavily applied had 

 prevented yellows and restored diseased trees. Two or three bushels were applied 

 for each tree, and the lime was spread broadcast over the whole ground. Every 

 tree thus treated was strong and healthy. President Barry thought that feeble- 

 ness of growth was sometimes mistaken for yellows, and that more credit might 

 have been given to remedies than they deserved. Dr. Hexamer mentioned 

 cases of success in treatment of yellows, where the soil was drawn away and hot 

 soap applied, the soap containing the potash required. Dr. Sturtevant explained 

 the nature of the action of the potash. In the yellows, the vessels become 

 overgorged with starch, and the circulation retarded or stopped ; the potash 

 dissolved it and set it free. This remedy had been worked out by scientific 

 reasoning, and was not the result of random experiment. Trees which have 

 been pronounced by distinguished authority as affected with the yellows had 

 been cured by this remedy, but continued experiment is needed. J. S. Wood- 

 ward said that the injury by the peach grub had been sometimes mistaken for 

 yellows, and he pointed out the distinction. He was willing to take all the 



