62 



SOME EXPERIMENTS WITH COMMERCIAL LIME SUL- 

 PHUR AS A SPRAY FOR FRUIT DISEASES. 



By H. H. Whe:tzkl, Professor of Plant Pathology, New York State 

 College of Agriculture. 



During the winter of 1908-09 there was much demand from 

 fruit growers for recommendations regarding the use of hme sul- 

 phur solutions as a summer spray. Plant Pathologists generally, 

 particularl}^ here in the East, advised growers to go slowly. If they 

 desired to try these solutions experimentally on a few trees, good 

 and well; but all were advised against the general use of this on 

 the foliage of their trees, until pathologists had time to determine 

 whether this could be done with safety and efficiency. The experi- 

 ments of Cordely in Oregon using the home boiled concentrated mix- 

 ture, and the work of Scott of the U. S. Department of Agriculture 

 with his self boiled lime sulphur, had been reported in the Horticul- 

 tural press and our Eastern growers wanted to know why it wouldn't 

 work here. This demand for information on the subject was the 

 more pressing for the reason that many growers had experienced 

 heavy losses from burning or russeting of the fruit by the Bor- 

 deaux. Naturally they were interested in a substitute that appeared 

 to be equally effective and at the same time free from the faults that 

 condemned the Bordeaux. 



In order to get some data on the value of lime sulphur as a 

 substitute for Bordeaux when used under our conditions in the 

 State of New York, wt undertook a series of experiments in an or- 

 chard near Ithaca, in the spring of this year (1909). Mr. Wallace, 

 a Fellow in the Department of Plant Pathology, had charge of this 

 work and to him belongs all the credit of the remarkable progress 

 \NQ have made on this problem this season. What I shall here re- 

 port is chiefly the results of his work. 



The work was conducted in two orchards containing several 

 varieties of apples, trees about 15 years old, with peach trees as 

 fillers. AVork on three diseases only were undertaken, namely, 

 Peach Leaf Curl, Apple Scab, and Brow^n Rot of the Peaches. A 

 field laboratory was established at Mr. Frear's place, in whose or- 

 chards the work was to be done. Commercial Lime Sulphur (Niag- 

 ara Brand, heavy grade) w^as used as this was what Mr. Frear 

 had already purchased for his winter spraying. Mr. Frear fur- 

 nished all materials, gasoline power sprayer, etc., and Mr. Wallace 

 assisted in all the application made. The work was very thor- 

 oughly done. 



Results on the Peach Leaf Curl. 



In these experiments comparisons were made between Bordeaux . 

 3-3-50 and different dilutions of the Commercial Lime Sulphur. On 

 account of heavy winds that blew constantly it was impossible to 

 spray the trees from but one direction. However as thorough a 

 job as possible under the circumstances, was done. The applica- 

 tions were all made before the buds had swollen to any appreciable 

 extent. Unsprayed check trees were left in every series of experi- 

 ments. The results showed that the Lime Sulphur at any dilution 



