VARIATION IN NORTHERN FOREST 869 



while in the other region the storms pass over or north of it, seldom 

 bringing rains from the east or northeast. Judged from the failure of 

 the three species mentioned as not reaching the Algoma region, the 

 humidity is less and probably the growing season is shorter. This is 

 borne out by the occurrence of three frosts in July and two early in 

 August of last year. No data on weather conditions were secured. 



Having shown the characteristic differences of the two regions. 

 the efiect on management of the forest may be noted. 



The black spruce swamps, having a wider range of site, have 

 greater stability than the softwood type of the Adirondacks which 

 contains a large percentage of balsam. This is the pure softwood type 

 in Algoma, becoming more pronounced to the northward as the prev- 

 alence of undrained bogs or muskegs supplants the better south- 

 ward drainage. Among ' softwoods out of the swamp type, where 

 balsam makes up a large part of the stand, the mortality is heavy in 

 the western forest, due chiefly to the attack of boring insects and 

 weakening of trees by butt and root rot. The forest of the spruce- 

 balsam type is constantly subject to this depletion, even in the virgin 

 stand, and this has resulted in the creation of a young forest, about 

 100 years old, as compared with an Adirondack stand over twice that 

 age. Due to its open condition, it is growing thriftily, has all size 

 classes well represented, and there is little acute suppression among 

 the young trees. This condition is not duplicated in New York, even 

 in the softwood type. The statement made for the softwood type 

 will hold also for the white birch mixture, while the stand having 

 yellow birch in mixture is not so severely congested as is the case in 

 more tolerant hardwood associations. 



Emphasis must also be given to the condition of long, softwood 

 crowns in the Algoma forest, since this factor enables the tree to recov- 

 er quickly when released. It must also be considered from the point 

 of fire hazard, since low crowns, combined with paper birch and prev- 

 alence of balsam increases the risk of destructive crown fires. White 

 cedar, scattered through the forest from the swamp edge to the high 

 ledges, since it is so liable to be hollow, holds fire over long periods and 

 prevents their final extinction. This species is less common in the 

 Adirondack region, and not so fire-resistant as the hemlock which it 

 replaces. 



The facts thus presented briefly, point -to certain advantageous 

 features in the Algoma forest which may be reviewed from the 

 standpoint of present management. 



