PAPERS ON BIOLOGY AND AGRICULTURE 83 



Passing north through the forest, the pitcher plants, swamp 

 sumach and cranberries gradually decrease and the blue- 

 berries increase. 



The northern part of this bog originally held a tamarack 

 forest, but the trees have been cut with the exception of a 

 narrow fringe on the east and northeast and the whole 

 northern third is now a blueberry heath of perhaps twenty 

 or thirty acres. Fig. 5. The floor is composed of peat but 

 is rather solid with occasional wet spots, and the dominant 

 types are blueberries and chamaedaphne with occasional 

 ledum and a shrub zone of chokeberry and occasional swamp 

 sumach around the outside. A small pond is reported in the 

 center of the bog but the writer did not have time to ascer- 

 tain its shape, size or other characteristics. On the north- 

 west side of the bog, the swamp formation from the south 

 narrows down and changes decidedly in the character of its 

 vegetation. A belt of shrubs and small trees is found next 

 to the tamarack forest, and between this and the shore is a 

 stretch of equal width covered with sedges and grasses. 

 This extends to the northwest corner of the depression, 

 but the tree zone seems to have been less extensive toward 

 the north consisting mostly of willows and has recently 

 been entirely cut away. 



The original oak hickory forest of the upland has been 

 almost entirely cut, but there are some patches remaining 

 on the hills to the southwest and northwest as well as the 

 clump previously mentioned on the morainal knoll in the 

 swamp. 



There was little opportunity to study the environmental 

 factors of this bog, but tests of acidity of the substratum 

 show it to be neutral for the tussock formation and for the 

 old moat on the west, of moderate acidity for the floor of 

 the tamarack forest and of the blueberry heath, and of a 

 slight alkalinity for the morainal slopes. 



4. Wauconda Bog. — This bog is situated in the south- 

 west quarter of Section 25, T. 44 N., R. 9 E., on the southern 

 outskirts of the town of Wauconda. The general shape and 

 location of the bog is similar to that of Volo, with a grass 



