10 



suitable weather conditions it becomes increasinglj^ marked as the 

 season advances. Hot, showery weather is ideal for the development 

 of the disease. Moisture is necessary for the germination of the 

 spores, and a high temperature favors the growth of the fungus. 



DEMONSTRATION SPRAYING FOR BITTER-ROT IN ARKANSAS. 



The demonstration work was done at BentonVille, Ark., and treat- 

 ment for bitter-rot was included in all the demonstration spraying at 

 that point, but only the results obtained in the orchard of Capt. George 

 T. Lincoln will be here discussed in detail. 



This orchard was not at first selected for the general demonstration 

 work, and it was not until July 10, after considerable infection of the 

 fruit had taken place, that spraying was begun. On July 6 Captain 

 Lincoln called our attention to a slight outbreak of the disease on his 

 Jonathans, and upon investigation on July 8 from 1 to 20 affected 

 fruits were found on each of various trees of the Jonathan, Gano, and 

 Ben Davis varieties, and on July 10 as high as 50 diseased fruits per 

 tree were counted on the Jonathan trees. The other variet}^, the 

 Givens, appeared to be free from rot at that time. Arrangements 

 were immediately made with Captain Lincoln for spraying a block of 

 250 trees about equall}' divided among the four varieties, and leaving 

 6 trees of each variety untreated as checks. Some of these check 

 trees were left together in two rows running a third of the way 

 through the block, near the center, while the others were distributed 

 in other portions of the block. The trees were ten years old and in 

 good condition, having been thoroughly pruned and well cultivated, 

 but during the past two seasons the orchard was in clover sod. 



The treatment. — The entire block, excepting the check trees, was 

 sprayed with Bordeaux mixture on July 10, July 26, and August 9, 

 and the Givens trees, which mature their fruit some three to four 

 weeks later than the other varieties, received an additional appli- 

 cation on August 27. The Bordeaux mixture was composed of 5 

 pounds of copper sulphate and 5 pounds of lime to 50 gallons of 

 water, to which 2 pounds of arsenate of lead were added for pro- 

 tection against the codling moth. The trees were thoroughly spraj'ed, 

 especial care being taken to reach every apple so far as practicable. 

 For the first two applications a good hand pump, mounted on a 

 100-gallon tank and equipped with two 30-feet leads of half-inch 

 hose and double Vermorel nozzles, was used. The other applications 

 were made with a gasoline-power sprayer, with a 200-gallon tank, 

 three 35-feet leads of f-inch hose, and triple Vermorel nozzles, a 

 tower being employed to reach the tops of the trees. 



The results. — Although the disease was well established in the 

 orchard before treatment was begun, the results were quite good, 



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