184 MASS. EXPERIMENT STATION BULLETIN 180. 



Beginning with the second decade in May, wet weather prevailed more 

 or less until about the 1st of August, culminating on July 24 in an all-day 

 rain in which 4.20 inches fell at the station bog in twenty-four hours, this, 

 because of the previous saturation of the ground, causing the streams to 

 rise so much that the bogs located in considerable watersheds were generally 

 flooded in spite of all efforts to keep the water down, 'It was estimated 

 that over 1,000 acres of bearing bog on the Cape, either in or a little past 

 the blooming period, were entirely submerged in this way. 



The wet season provided unusual chances to study the effects of water 

 on the blossoms and small berries. As a rule, the bogs bloomed heavily, 

 and for a time a record-breaking crop was expected, but an unusually 

 large proportion of the blossoms failed to set fruit. This failure took place 

 especially among the under berries, for the crop turned out to be more 

 "on top" than usual. Almost no berries were commonly found in thick 

 clumps of vines where the blossoms had been very abundant, while in thin 

 vines near by there was a fair amount of fruit. These conditions were gen- 

 eral, though less so on bogs that either had no winter-flowage or had it 

 taken off early. The wet weather evidently caused this failure of the set, 

 though it is hard to say definitely how it did so. The rain may have pre- 

 vented a proper fertilization of the flowers either by washing off the pollen 

 or by preventing bees from working actively. Perhaps an unusual preva- 

 lence of fungous diseases induced by the excessive moisture blasted the 

 blossoms. 



It is the wi'iter's present opinion, based on general observation and ex- 

 perience, that late holding of the winter-flowage so throws the blossoming 

 period out of its normal season that the danger of its meeting unfavorable 

 conditions for the setting of the fruit is usually considerably increased 

 thereby. 



That flooding when the berries are small is dangerous was shown by the 

 effects observed on some bogs submerged for not over fifteen hours with 

 the blooming period past and crop fully set. These bogs lost half their 

 berries in spite of the cloudy weather that prevailed when the water was 

 let off and for three days afterward. The largest of the berries injured 

 under these circumstances were somewhat over a quarter of an inch in 

 diameter. Many of the larger berries on some bogs, however, endured 

 submergence two or three days without apparent injury. 



Frost Protection. 



In the fall of 1915 tests with new tobacco cloth, used in various ways on 

 a bog with much moss under the vines, showed no considerable temperature 

 advantage. 



In the spring of 1916 this cloth was tried on a bog that was fairly well 

 sanded and with only a little moss. Green registering thermometers were 

 used in all the tests. Under one thickness of cloth spread on the vines 

 they showed a higher minimum temperature than thermometers not cov- 

 ered, — by 3 degrees in some cases, though the usual difference was less 



