THE GIPSY MOTH ON CRANBEREY BOGS. 17 



CONTKOL ON UPLANDS. 



After the gipsy moths have reached the second stage, and 

 all danger of wind dispersion is reduced to a minimum, heavy in- 

 festations may occur on the uplands in the vicinity of cranberry 

 hogs, and if heavy enough to cause defoliation the caterpillars, in 

 their march for a supply of food, may move in the direction of a 

 bog, and owing to the large amount of food necessary to maintain 

 the hordes of larvae, may become a serious menace to the bog itself. 



There are several methods of control that may be used to advan- 

 tage in such an emergency, and one or more of those mentioned below 

 should be adopted in order to protect the bog. 



The woodland border of the bog may be cut back for the space 

 of 100 feet or more, and possibly the section of woodland from 

 the edge of this cutting to the infested area may be sprayed. If, 

 however, this distance should happen to be only a few hundred feet, 

 the spraying would not accomplish the desired result, because only ?.. 

 few of the thousands of larvse present would consume enough 

 of the poisoned foliage to cause death. The others would march on 

 in search of more food. 



When such conditions occur, an open ditch on the upland, back 

 from the bog border, may be dug, 12 to 15 inches deep and 18 inches 

 wide, the earth being thrown toward the oncoming horde of larvae, 

 and the side of the ditch nearer the bog being made perpendicular. 

 At the top of this perpendicular side a board about 1 foot wide 

 should be placed at an angle of 45 degrees, overhanging the ditch, 

 supported by stakes driven into the soil; earth should be banl?:ed 

 on the outside of this board in such a way as to close up all spaces 

 at the base of the board caused by the irregularities of the surface 

 of the ground. The undersurface of the board and supports should 

 be well smeared with a commercial sticky tree-banding material 

 before being placed in position. The larvae upon reaching this band 

 will fall into the ditch, and should be sprinkled with crude oil from 

 an ordinary watering pot. In case of extremely heavy infestations 

 it may be necessary to clean out the mass of dead larvae before the 

 last hordes reach the ditch. (Fig. 4.) 



If a protective belt is already cut around the bog it is highly 

 desirable that all sprout growth be kept down by bruising the sprouts 

 from the stumps for two or three years, using a dull ax with which 

 to perform this operation, mowing all other small growth close to 

 the ground, and burning all the debris. This well-cleaned border 

 may help greatly in controlling some of the other insects that breed 

 on the upland border, thereby reducing their ravages on the bog 

 itself. 



