- 57 - 
ive mosaic 1-2 dm, above the surface, enabling more 
aesophytio species to start# .associated with these in 
varying proportions are tho brake ( uteris aoqullina h.), 
the sulmonberry ( Rubus parvifloruo Butt.) and the bush 
honeyoucklo ( Mervilla Lonicora rill#), the latter often 
being very common on the upper, dryer portions of the 
slope. 
The pioneer tree growth consists of small soattered 
individuals# If white birch be the pioneer spoolos, which 
seems not always to be the oase, it is soon followed by the 
poplar spocios alroady mentioned and by scrubby specimens 
of red oak# Besides many seedlings of the above, several 
other woody species appear more or less during the early 
stages of invasion such as hop hornbeam ( Ostryi virgin! an a 
frill #) k# koch#), arrow-wood ( Viburnum dent-turn L«)» choke- 
cherry ( krunus virglnlana L»). buffalo-berry ( Shepherd!a 
canadensis (L.) Butt.), Rubus procumbens lluhl., Rosa acicul - 
aris Lindl#, and seedlings of basswood, white ash and sugar 
mapla# 
Burly herbaceous species, as such, hardly form a 
definite stage in the succession in the sense of paving the 
way for woody growth# They may precede or accompany tfco 
latter, but are lator controlled by reaction# among the 
oonmoner species may bo mentioned Brigoron canadonsis L. 
