31 



(2) Make no one bog so large that more than thirty-six hours are 

 required to cover completely, and no more than twenty-four hours are 

 required to draw the ditch level. 



(3) Build a reservoir or reserve a flooded area above the level of the 

 highest bog of a series sufficient to hold water enough to flow at least 

 the highest bog completely. The importance of this requirement is 

 so fully appreciated that miles of ditches have been dug in New Jersey 

 to tap streams at a higher level, and many acres of swamp area have 

 been created by raising contour lines to deepen natural basins. In 

 Massachusetts powerful pumps have been installed to pour water 

 directly upon the bog or into a reservoir above it. 



(4) Adjust bog levels so that the upper one of the series can be com- 

 pletely emptied into the one below, and yet have the gates and outlets 

 so adjusted that any one bog may be completely emptied without inter- 

 fering with either those above or those below. It happens not infre- 

 quently that one bog needs cleaning or other attention while others 

 do not. 



(5) There should be a broad, deep, marginal ditch between the dam 

 and the bog or between the bog and upland, and this ditch should be 

 always clean and at least partly full of water. Many kinds of insects 

 can be altogether kept from the bogs in this wa}^, while grasshoppers 

 and other insects are delayed until they can fly. Then they are feed- 

 ing on other things, and they do not often change the food habits of 

 their early life. 



(6) The dams and the edges of the uplands should be kept as free as 

 possible from vegetation that harbors cranberry-feeding species. 

 Cranberry vines should not be tolerated for an instant. Huckleberry 

 bushes are almost as bad, and these should be cleared back for some 

 distance where bog and upland join without an intervening dam. 

 Other heath plants are also undesirable and should not be allowed too 

 near the bogs nor on the dams. 



(7) It follows from what has been said that the bog itself should be 

 kept as free as possible from all plants other than vines, certain grasses 

 being especially objectionable because they are used by long-horned 

 grasshoppers as places to lay their eggs. 



Bogs so arranged could be kept completely safe at all times, and 

 once properly laid out would require little outlay to keep them so. 

 The question whether bogs should be kept wet or dry, whether there 

 should be manj^ or few ditches, and whether these should be deep or 

 shallow need not be here considered at all. The dates of flowage and 

 reflowage and other points of measurement b}'^ means of which con- 

 trol may be made effective have been already touched upon. 



The important advantages are that neither insecticides nor spraying 

 machinery would ever be required, and the insect problem would be 

 reduced to the simplest possible terms. 



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