ENTOMOLOGY 95 



The third crop of moths appears late in July or early in 

 August and are of the same orange-red color as the second. Eggs 

 laid by these moths do not hatch until in August or even early in 

 September, and the worms that come out of them grow slowly as 

 compared with the earlier broods. Few of them spin up more than 

 a single shoot and few of them eat into any but the smallest berries. 

 They also tend to become reddish in color and even striped, so that 

 at one time they were believed to form a distinct species, described 

 as the red-striped cranberry worm. Not until after the picking, 

 if anything be left to pick, do these worms become full grown. 

 Very irregularly in late September and early October they come 

 to maturity, and now the moths that come from them are, after 

 a dust of orange wears off, of the slate-gray color seen in spring. 



The application of insecticides on large bog areas where the 

 plants cover the ground as densely as do the cranberry vines is a 

 task no grower likes to contemplate; and provided he has control 

 of a satisfactory amount of water there is no necessity for it. As 

 against the yellowhead it will suffice if the water be held on the 

 bogs until the middle of May, or perhaps a little later in cold sea- 

 sons. By this time the huckleberry and heath plants have made a 

 good growth and have tempted the hibernating moths to lay their 

 eggs. Unless, therefore, the vines are uncovered at the edges or 

 on knolls above water, the plants will be free from the first brood 

 of worms. In the woods and on the upland plants the worms and 

 even the moths are exposed to the attacks of birds and many preda- 

 tory insects that never go upon the bogs; hence the adults of the 

 first summer brood will not be nearly as plentiful as if they had 

 bred on the vines. Only a few, comparatively, of the moths will 

 fly upon the bogs, and even then do not usually get very far from 

 the edges; so that the heavy, very injurious middle brood will be 

 reduced to practically harmless numbers. The third brood, 

 even if it does spread over a greater area, is not likely to prove 

 troublesome, for reasons already stated. Hence, care and attention 

 to the drawing of the water in spring will of itself suffice to keep 

 this insect in check. If to this we add the destruction of the heath 

 and huckleberry plants immediately surrounding the bogs, the 

 nearby breeding places are further reduced and the bog is the more 

 likely to remain free. 



As against the blackhead late holding will not of itself suffice, 

 because the eggs are already on the plants and will, under ordinary 

 circumstances, hatch only under the same conditions that favor the 

 start of vines themselves. But there is a little leeway in favor of the 

 plants, and the eggs do hatch under water at a temperature not 

 quite sufficient to start the vines. To hatch the eggs the proper tem- 

 perature only is needed; to start the vines there must be also sun 

 and air. If, therefore, a bog is tolerably level the water may be 

 drawn from below until it just covers, and may be held there even 

 after May 15, until the starting of the vines indicates that the dan- 



er point has been reached, and then it must be drawn to avoid 

 illing the fruit buds. Runners or laterals not bearing fruit buds, 



