COLLOIDAL PROPERTIES OF BOG WATER 



George B. Rigg and'T. G. Thompson 



Introduction 



This paper is a report of work on the chemical analysis of 

 bog water, the colloidal state of the material in the water, and the 

 effects of this material on the growth of plants. Much of the 

 work is now reported for the first time, but a brief general state- 

 ment of some of it has been made in a former paper (13). It is 

 also shown how the data here given tend to ekplain current agri- 

 cultural practice in bog utihzation. 



Sphagnum bogs are very numerous in the Puget Sound region 

 and in Alaska. There is scarcely any portion of western Wash- 

 ington in which they are not found, and in some cases there are 

 continuous areas of approximately 300 acres. The fact that these 

 bogs act as a selective habitat and have a peculiar flora of their 

 own, largely xerophytic, makes them objects of great botanical 

 interest, while the fact that the substratum in them, often to a 

 depth of 30 ft. or more, is composed almost entirely of organic 

 matter, and that they have little or no forest covering, makes the 

 utilization of these areas for agricultural purposes a matter of 

 peculiar economic interest. 



The acreage of these bogs now utilized for cranberry culture 

 and for gardens, meadows, and pastures, although considerable, 

 is still very small in comparison with their total area in the region. 

 Every bog is a potential crop-producing area of considerable 

 importance, and whatever we can learn with regard to the funda- 

 mental factors that govern the growth of plants in bogs in their 

 natural state may function in their transformation into areas in 

 which food production in this region can be increased. 



In former papers the senior author has described the flora of 

 some sphagnum bogs of the Puget Sound region (10) and Alaska 

 (11), and has summarized and discussed the various theories (12) 

 that have been suggested to account for the peculiar character of 



267] [Botanical Gazette, vol. 68 



