- 58 - 
(horseweed), Silene antirrhina L. (sleepy catolifly), Satur - 
oj a vulgaris (L.) Fritch. (basil), iiralia hispida Vent* 
(bristly sarsaparilla), Convolvulus spithamaeus L. (ereot 
bindweed), Carey adusta Boott., Antennaria neodioiea Greene 
(everlasting). Frag aria vasca L. var. amerioana Porter (wild 
strawberry), Bpilobiuro angustifolium L, (fireweed), Adlumia 
fungosa (ait.) Greene (climbing fumitory), Apocynum androesimi - 
folium L. (spreading dogbane) and Campanula rotundifolia L. 
(harebell). 
The sequence of the invading associations varies greatly 
at different points along the range. While Betula alba var. 
papyrifera is the dominant pioneer tree species at some points, 
at others it is Populuo tremuloides or Populus grandidentata . 
The exact ecologioal relationship between these three speoies 
is an interesting problem, but it was not worked out. Even¬ 
tually the invading forest merges with the permanent fringe 
of forest below the talus. The latter is often dominated 
by sugar maple and red oak, but here again considerable var¬ 
iation occurs, which will be considered later. 
(4) Forest below talus slope. 
This extends in general from the flood 
plain of the valley below to the bottom of the talus slope 
above, pushing up tov?ard the summit or even reaching it at 
low points in the range. It may vary in width from a mere 
