16 



providing for as good a control of the water as possible. Under proper 

 control the water ma}'^ be drawn from the bogs when the best interests 

 of the plant demand it without an}^ regard to insect conditions. If 

 worms appear in any number toward the end of May, the bogs are 

 reflowed, and rarely is this necessar}' more than once in three years. 

 Onlj^ when the bog area is small and the surroundings are very bad is 

 annual reflowage needful. For a complete effect the vines should 

 remain covered forty -eight hours, because it requires some time for 

 the water to penetrate the spun-up leaves so as to kill the worms. 

 Man}^, indeed, especially the half -grown blackheads, wriggle out, 

 seeking to escape when the water reaches them, but those nearing 

 maturity are less active, remaining at home until the water surrounds 

 them and they simply can not get out. Covering the bogs should 

 begin in the late afternoon and should be completed before next morn- 

 ing, if possible. On a rainy day it may begin at any time, the object 

 being merely to prevent the sun from boiling the j^oung shoots. So 

 drawing off the Avater should also begin in the early afternoon, and the 

 bog should be practically dry the morning after. Incidentall}^ this 

 reflowing will rid the bog of numerous other pests and ma}" make a 

 material impression on the girdle worm where that is abundant. 



The importance of a sufficient water suppl}' has come to be so gen- 

 erally recognized among advanced growers that in New Jersey miles 

 of ditches tap streams far away from the bogs, and in Massachusetts 

 expensive pumping machinery has been installed to raise water in 

 large quantities to high-l)og areas. 



It is sometimes possible to use the upper one of a series of bogs as 

 a reservoir, holding a full head of water as late as it is safe to reflow 

 the lower bogs of the series which have been drawn early. In one 

 series of 100 acres, divided into 5 sections by cross dams, a fall of 

 about 10 feet is utilized to reflow all save the uppermost section, and 

 this practice is possible in almost ever}^ case where water is available. 



Insecticides. — Sometimes it happens that bogs can be neither winter 

 flowed nor reflowed, and the application of insecticides becomes an 

 absolute necessity. Only arsenites are to be relied upon for good 

 results, although for a long time tobacco was and in some parts of 

 Massachusetts is yet the main reliance. It follows from what has 

 been said concerning the habits of the worms that when once they 

 have spun up the tips and are feeding in their cases they are practi- 

 call}^ beyond the reach of our common insecticides; and that is partic- 

 ularly true of the first brood. If there is reason to believe from past 

 experience, or because eggs have been found on the plants, that the 

 early brood will be numerous, spra3'ing must be done just as soon as 

 the vines make a start or not later than the date when the first spun-up 

 tip is seen. The object is to get the poison into position before the 

 leaves are spun up, so that the worms may find their first meal poi- 



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