1899] INE 
DUNE FLORAS OF LAKE MICHIGAN 
375 
great majority of rej 
juvenated dun 
Bt conit es are developed from 
r.., a dunes ; hence this type is i in — 
Ae T a ° nf 
Bn the — series. The coniferous forests ae 
struction ibd slopes near the lake are peculiarly sub 
2s . e slightest ch ; 
ee ten s s change in the physical condi- 
sufficient to bring about the Paes of ; 
a 
F 
Gras 
Amm . 
ophila q : 
un 
back, Advance Ae = ee Patches of bearberry 
the coniferous forest out upon the heat : 
North Manitou island. 
he foreground. Low 
heath forming farther 
"et May be ie ‘ The removal of a comparatively slight bar- 
ugh to direct the entire wind energy against a 
pine f 
Orest 
s, the most common 
a windward slope 
enated at three 
ser range in fig 
height, and the 
The ; 
Way for Sg of a wind-sweep is, perhap 
‘tanted - to begin. Fig.'6 shows 
Points, ey conifers that has become rejuv 
*l. This Ng these wind-sweeps is seen at clo 
er sweep is forty-five meters in 
