BASIC COPPER SULFATE AS A FUNGICIDE V.V.\ 



obtained by increasing the dilution of the previous mixture. For apples a large- 

 sized Friend spray apparatus, under 300 pounds pressure, with two Boyce guns, 

 parallel nozzles and s^-inch discs was used. Prepink (May 7), pink (May 13), 

 and calyx (June 2) appHcations were made of about 6 gallons to a tree. Basic 

 sulfate failed to control scab as effectively as liquid Ume-sulfur, injured the foliage 

 and russeted the fruit. The latter was not particularly serious with the lowest 

 concentration. 



For plums and grapes a 50-gallon hand outfit, under approximately 175 pounds 

 pressure, equipped with rod and disc nozzle, was employed. The plums were 

 sprayed on May 24 and June 8 and the grapes on May 19, June 8 and July 17. 

 Roberts reported that the spreading and adhesiveness of basic sulfate appeared to 

 be satisfactory. The effectiveness could not be determined as there was practi- 

 cally no disease present. FoUage injury was observed on aU the plants sprayed, 

 increasing with concentration, but evidently was not appreciable on the fruit of 

 plums and grapes. 



Miscellaneous 



Dr. W. P. Brooks of Amherst sprayed currants, English gooseberry, nine varie- 

 ties of grapes, tea roses and plilox vrith. basic sulfate 4-50 with combined spreader 

 and did not observe any foliage injury. 



L. F. Kinney of Ivingston, Rhode Island, sprayed seedlings of Rhododendron 

 Cataivbiense in flats with basic sulfate 2.5-50 without injury. 



Field Work in 1927 



The field work of 1927 with basic copper sulfate includes experiments with 

 cucumbers and celery at the Market Garden Field Station at Waltham, with 

 potatoes on the Experiment Station plots at Amherst and on the farm of G. Fred 

 Pelissier at Hadley, and mth apples and grapes in the College orchard and vine- 

 yard. The basic sulfate wasJappHed both as a spray and mixed with a free-flowing 

 talc as a dust. The experiments with cucumbers and celery were conducted by 

 E. F. Guba as in previous years. 



Cucumbers 

 The objective was to determine the relative eflficiency of spray and dust applica- 

 tions of basic sulfate in controlling anthracnose and mildews on cucumbers. The 

 experiment consisted of 3 plots, 120 by 12 feet, of 2 rows each, planted in hills 6 

 feet apart each way. Several preliminary treatments were found necessary to 

 control insects. Bordeaux 4-4-50 was applied for flea beetles after the first 

 leaves appeared (June 8) ; sodium fluosilicate dust for striped beetles on June 17, 

 21 and 30 and July 8; and lead arsenate, lime and nicotine sulfate 1.50-2-0.5 

 pt.-50 for striped beetles on July 14. The regular spray consisted of basic sulfate 

 (lot 5), lead arsenate and raw linseed oil 2-1.5-0.5 pt.-50 and contained about 0.26 

 per cent copper and 0.07 per cent arsenic. The dust consisted of basic sulfate 

 (lot 5), lead arsenate and talc and contained about 7.02 per cent copper and 4.01 

 per cent arsenic. The plants were treated on July 21 when vining began and on 

 July 28 and August 4. A 3-gallon knapsack sprayer and a 2-quart Feeney duster 

 were employed for application. The spray left a thin, hardly perceptible residue 

 which disappeared entirely after the least rainfall. The oil was not found satis- 

 factory as a spreader or adhesive. Dusting resulted in a heavy deposit on the 

 foUage and protection of the lower surface of the leaves. Neither appKcation 

 caused perceptible injury. The vines made a poor growth due to severe stunting 

 and foliage injury resulting from applications of sodium fluosilicate from which 



