Nov., 1910.] 
A Cedar Bog in Central Ohio. 
J 95 
of arborescent plants, bog relicts, weeds, and invading plants has 
established itself. But even under such conditions an order of 
invasion and succession is to a certain extent characteristic in the 
movement of plants, and depends largely upon the extent to which 
the plants are especially enabled to cope functionally with the 
changing conditions and hold their ground. The time and chance 
factors, i. e., the opportunity for occupancy of the area, the 
relative amount of filling, and the degree of decomposition of peat 
which has occurred in the basin, are of equal importance in com- 
petition and maintenance. In all cases and at all times during 
the phases of the development of a plant formation the invasion, 
zonation, and succession of plant societies is intimately bound up 
with differences in available soil water content, and available food 
constituents which go concomitant with the degree of the 
decomposition of peat soils. 
The most interesting of the many different kinds of bogs in 
Ohio is a Cedar bog near Urbana in Champaign County about 
forty miles west of Columbus. In a few places the character of 
the county is hilly, and in the depressions occur peat deposits. As 
a whole, however, the surface of the county is level and made up 
of plains. The general form is that of a broad shallow trough, 
lying north and south. Mad-River runs through the middle of 
it, and drains the main body of the territory. 
On the east side of Mad River, in the southeastern part of 
Mad River Township, and extending largely over into Urbana 
Township (TfiRl 1) in sections 31 and 32 is a tract of land known 
as the Dallas Cedar swamp. It is about six miles south of Urbana, 
and easily reached by means of the Ohio Electric Railway. The 
Cedar Swamp is a part of an area of cleared bog which comprises to- 
day about GOO acres. There was once an extensive deposit covering 
approximately 7,000 acres. On a small portion of land owned by M. 
and G. L. Dallas occur as described below groves of arbor vitae 
(Thuja occidcntalis) in a good state of preservation. The groves 
occupy a habitat near which the soil water is derived from cold 
springs along the poorly drained river valley. A considerable 
number of soundings were made which disclosed for the first two 
feet a blackish brown compact, well decomposed, non-fibrous 
peat. At the third foot level the peat appeared dark brown, some- 
what fibrous, with a considerable admixture of marl below. A 
number of well preserved logs and branches were encountered. 
At four feet the peat appeared brown and compact but fibrous in 
texture with fragments of rhizomes and roots. At the five feet 
level the sounding instrument encountered a coarse gravel with 
stones showing glacial striations. This rested on beds of quicksand 
and morainal till. The bog harbors a unique dependent flora which 
long throve here un nolested and was once a favorable resort for 
botanists. Now the cedars and the accompanying undergrowth 
