54 MASS. EXPERIMENT STATION BULLETIN 355 



season in the proportions of dry lime-sulfur 3 pounds and sulfur 5 pounds per 

 100 gallons in the pre-pink and pink, dry lime-sulfur 2 pounds and sulfur 4 

 pounds in the calyx, and dry lime-sulfur 1 pound and sulfur 4 pounds in the 

 cover sprays. Variations of the standard schedule were also tested. Micron ized 

 sulfur and both the paste and dry forms of flotation sulfur were applied following 

 liquid lime-sulfur in the calyx and pre-blossom sprays 



Lead arsenate was used in all cases at the strength of 3 pounds per 100 gallons 

 in the pink and 3d cover sprays; 4 pounds in the calyx, special curculio, 1st and 

 2d cover sprays; and 2 pounds in the 4th cover spray. It was omitted in the pre- 

 pink application. Owing to the unusually early season the 1st cover and previous 

 sprays were applied from 7 to 10 days in advance of the normal dates for those 

 applications. To compensate for such conditions and to make succeeding sprays 

 conform to the usual schedule, a special application was made for curculio con- 

 trol. Linseed oil as a sticker was used in the 1st cover and special curculio sprays. 



Examination of the trees in the experimental plots in late May showed that in 

 all plots on which liquid lime-sulfur had been applied according to the standard 

 program there was considerable crinkling of the leaves with some marginal burn, 

 particularly as a result of the calyx application. No scab spots were observed 

 even in the tops of the trees. The foliage on the trees which had been sprayed 

 with diminishing strength of lime-sulfur showed as much injury as that on which 

 standard strength of lime-sulfur had been used. In the plots where lime-sulfur 

 with spray catalizer and dry lime-sulfur with sulfur had been applied, there was 

 less foliage injury, as regards both crinkling and marginal burn, than where liquid 

 lime-sulfur was used. There was no evidence of scab in any of these plots. On 

 both the Mcintosh and Baldwin check trees there was no crinkling of the leaves 

 nor other evidence of spray burn. There was considerable evidence of scab on 

 unsprayed Mcintosh trees. Leaf roller, tent caterpillar, gypsy moth, and bud 

 moth were found on the unsprayed Baldwins. 



On May 15 there occurred a brief storm which was accompanied by high winds 

 and was, in effect, a mild foretaste of the September hurricane. Many trees were 

 blown down, and on the east and southeast exposures much foliage was badly 

 wind-torn. Undoubtedly some spray burn was masked by the browning of foliage 

 resulting from this wind injury. 



On September 10 the experimental plots were inspected to note comparative 

 effects of the different sprays upon fruit and foliage just before it was anticipated 

 that harvesting of the Mcintosh would begin. The unsprayed Mcintosh trees 

 showed much scab on foliage. Practically all the fruit was infected and many 

 apples were badly cracked. In the dry limc-sulfur-sulfur plot there was a con- 

 siderable amount of foliage injury and russeting of fruit. In the other plots there 

 was almost complete recovery from early burning and practically no late summer 

 injury or russeting of fruit. A somewhat blotchy spray deposit on fruit was 

 noted in the plots where flotation sulfur was used, but no russeting occurred. 

 Very little scab was noted on either fruit or foliage. On Baldwins the dry lime- 

 sulfur-sulfur combination caused considerable leaf burn and slight russeting of 

 fruit. A much milder type of injury was noted on the foliage in the lime-sulfur- 

 spray catalizer and diminishing strength lime-sulfur plots, and no russeting of 

 fruit. Practically no injury was noted on the flotation sulfur plots or on the tiees 

 given the standard schedule with micronized sulfur in the sprays following the 

 calyx. 



No record of harvested fruit could be made. The hurricane of September 21 

 blew off all the fruit and broke down many of the trees in the experimental block. 

 The high wind also scattered the fruit so generally from one plot to another that 

 it was impossible to determine whether the apples under one tree dropped from 

 that tree or were carried from one several rows awav. 



