148 



130 acres of the scarlet oak woodland, there were found 355 

 species of plants. 



In the scope of this paper it will be necessary to mention but 

 a limited number of the more characteristic forms. Nowhere 

 is the fact more plainly emphasized than here, that the ex- 

 posure is a dominating factor in determining distribution of 

 plant life. In this association type it is only on northeasterly 

 slopes that the yellow lady slipper {Cypripedium hirsutuin) is 

 found, and then only in dense shade. This species is very local, 

 not more than one or two "patches" being found in a town- 

 ship, and it is always in close proximity to the two ferns 

 Osmiinda Claytoiiiana, and Aspleniuiii Pilix-foeuiina, botli in 

 great abundance. These patches are invariably in the moist 

 rich shade of ravines having an eastward trend. The tway- 

 blade (Liparis lilia folia) is a rare associate, and Habenaria 

 bnicteata and Orchis spcctubilis are yet rarer. It is worth re- 

 cording here that the last species was found by me in 1891 

 in identically the same situation and exposure, three miles south- 

 west of Lewiston, h\ilton County, growing so abundantly as to 

 tint the woodland with its beautiful colors. Other species not 

 so "finicky" as to exposure arc TriUinin, dccliiiatum, Uvtilaria 

 grandiflora, Allium tricocciuii, Podophylluin, (leranium macula- 

 turn, Dcsmodium grandifloruui , I'iola sororia, Saiiicula canadensis, 

 Osmorhisa, Aralia racemosa, Steiromnia ciliatum, Triostium 

 aurantiacum. 



On the flattened crests of nearly all the watershed ridges, 

 or rather, in many cases, the broad elevations between adjacent 

 streams are poorly drained areas, thin-soiled as a rule, and oc- 

 casinally with a small circular pond, the remains of an ancient 

 "buffalo wallow." These tracts are the ideal home of the aspen- 

 poplar association. They arc generally of small extent, but 

 now and them assume the ])roportions of a respectable wood- 

 land. The individual trees are commonly scattered, though not 

 infrequently forming dense growths. Here and there are small 

 0])en spaces surrounded by luxuriant clumps of hazel, which 

 send out arms and straggling bands among the asj^ens. Prac- 

 tically the only other woody ])lant of size is the pussy willow 



