REPORT OF THE STATE ENTOMOLOGIST 1905 



"3 



surrounded that a journey of miles in almost any direction will 

 bring one to a salt marsh. More unfavorable conditions for mos- 

 quito control could hardly be found, and before this work was 

 attempted mosquitos swarmed in the village in May and remained 

 in numbers most of the season. The second year swarms did 

 not invade this territory till June, and last year it was the first 

 of July before they appeared. Our investigations at the end of 

 last July showed that there were practically no mosquitos in the 

 center of the village. It was our privilege to sit on a piazza one 

 evening when conditions were most favorable for mosquito activity. 

 Though it was cloudy with only a little breeze and rather warm, 

 not one appeared. Previous to this antimosquito work it was said 

 that one could not sit on this piazza without being covered by 

 netting, and the owner even went to the trouble of making a frame- 

 work to hold netting suspended over individual chairs, so that his 

 family and guests could sit in comfort. 



This very desirable result has been brought about by a drainage 

 system so planned that the entire length of all ditches will be flushed 

 by every tide. The general practice is to run these ditches within 

 about 200 feet of firm ground and sometimes closer, making them 

 18 to 24 inches in width, from 2 to 3 feet deep [pi. 8, fig. 2], with 

 main ditches here and there to tidal channels. A few headland 

 ditches are run into the more dangerous swampy areas in baylike 

 extensions of the marsh. Such ditches require no surveying and 

 cost only \]A cents a running foot. A littie experience enables one 

 to lay them out properly and the tides make the determining of 

 levels extremely easy. It was very interesting to compare the 

 conditions between ditched areas and undrained marshes. The 

 former were so free from mosquitos that one could tramp upon 

 them with practical immunity from bites, though occasionally a 

 few mosquitos were seen on one's person. No larvae were found 

 and in fact there were very few places where breeding was possible. 

 Undrained marshes presented a very different condition. Mos- 

 quitos swarming in adjacent woodlands made driving very uncom- 

 fortable, and when on the marshes one was attended by considerable 

 swarms of vicious biters, even in midday. Here and there breeding 

 pools were literally black with young wrigglers. This contrast 

 between drained and undrained areas would doubtless have been 

 much greater were it not for the act that our inspection was made 

 during such a dry time that even undrained marshes presented 

 comparatively few favorable breeding places. 



