270 BOARD OF AGRICULTURE. [Pub. Doc. 



reflow should probably, as a rule, be postponed to some time 

 during the second week of the month. 



If frost threatens to do damage during May or the first half 

 of June, it will be necessary to put on a partial flood for pro- 

 tection against it. It is not necessary, however, to entirely 

 cover the vines for frost protection. Two or three inches of 

 water over the surface of the sand under the vines is entirely 

 sufficient for this protection, as the water will radiate its heat 

 into the air and maintain a sufficiently high temperature 

 around the vines to keep them from freezing. Bogs are flooded 

 both by gravity flowage and by pumping. With many bogs, 

 however, there is not sufficient water supply for reflowage or 

 even, in some cases, for winter flowage. On such bogs, if they 

 are not located in exceptionally cold places, protection from 

 frost may be had at reasonable expense by the use of tobacco 

 shade cloth. 



The bog should not be reflowed during or after the blossom- 

 ing period except in cases of extreme need, such as protection 

 from a forest fire or a threatened insect devastation which 

 evidently could not be averted in any other way. In Septem- 

 ber and October the fall period of frost danger often makes it 

 necessary to again flow the bogs for protection. The berries 

 and vines will, however, endure some frost at this period of the 

 year, and longer chances may be taken than during the spring 

 period of danger. It is not desirable to flood in the fall for 

 protection if it can be avoided, for the water tends to cause a 

 deterioration in the keeping qualities of the fruit. It should 

 be stated, in this connection, that it is best not to flood for 

 frost protection either in the spring or fall unless it is certainly 

 necessary, for the water at either period of the year will do a 

 certain amount of harm. The United States Weather Bureau 

 maintains a frost-warning service for the benefit of the growers 

 during both of these periods, and warnings may be had from 

 the office in Boston when they are needed by any grower if he 

 has a telephone and will make his wants known. It is not wise, 

 however, to always rely absolutely on this service, but most 

 growers could save their bogs from many a flooding, and at 

 the same time save their water supply to meet their greatest 

 needs when such supplies are not abundant, by making a more 



