GIPSY MOTH WORK IN NEW ENGLAND. 23 



Where small white pines have occurred in any quantity they have 

 been counted and the numbers have been recorded by foot-height 

 classes. The best available indication of the degree of gipsy-moth 

 infestation seems to be the number of egg clusters, and for this 

 reason the egg clusters have been counted on each plat. Egg 

 clusters will be counted periodically in the future in order to determine 

 the effect of treatment upon the infestations. 



After the foregoing steps have been taken, the growth on each of the 

 managed areas has been thinned. Different silvicultural systems have 

 been used, but in general the object has been to remove the greatest 

 number of susceptible trees consistent with the silvicultural require- 

 ments of the trees to be left. In some cases the bulk of the stands 

 consisted of susceptible species, and in these the thinning made was 

 preliminary to a later clear cutting. 



After cutting, the number of trees of different diameters and species 

 have been counted and recorded, the amounts of products have been 

 measured and recorded, brush has been piled and burned, careful 

 notes of the changed conditions have been made, and an effort has 

 been made to compute the cost of the work and the value of the prod- 

 ucts on each plat. In some cases numbers of small naturally pro- 

 duced white pine have been supplemented with planted 2-year-old 

 seedlings from the nursery. In cases where plantings were made the 

 cost of the seedlings and the planting was borne by the owner of the 

 woodland. In addition to the sample plats already mentioned, one 

 10-acre tract has been selected in each of the following towns in New 

 Hampshire: Peterboro, Franklin, Warner, and New Durham. The 

 growth on all these plats is largely inferior hardwoods which are par- 

 ticularly liable to gipsy-moth attack. The infestation in each case 

 is not heavy. As there is more or less white pine growing among the 

 hardwoods the plan is to cut the latter clean and to replace these 

 trees by planting enough white pine to produce a stand which will be 

 free from gipsy-moth damage. The results of these experiments will 

 not be available for several years, and during this period careful notes 

 on conditions will be made. 



MIDDLESEX COUNTY FOREST SURVEY. 



In order to get some definite information concerning the distribu- 

 tion of the various kinds of timber stands in the region, a rough forest 

 map of the county of Middlesex in Massachusetts has been made. 

 This work has shown that the forest growth is very uneven and com- 

 plex, and that there is a wide variation in the composition of stands 

 within relatively small areas. The existing growth of trees on any 

 area indicates very infrequently the growth for which the conditions 

 on the area are best suited. From data secured by this survey and 

 observations made througthout the infested region, the crying silvi- 



