80 
IOWA ACADEMY OP SCIENCE 
THE BELT TRANSECT. 
An idea of the character of the region is best indicated per- 
haps by a detailed study of a belt transect or strip across some 
part of the area representative of the diverse conditions which 
give “The Ledges ’’ their peculiarity. The belt chosen extends to- 
ward the southeast from the bank of Pease creek, up the north- 
facing hillside, over the ridge or hogback and down the south- 
facing slope to Pease creek. The belt is represented on the map 
(fig. 1) as a black block. 
Fig. 2. — Diagram showing the relative location of the various plots in the 
strip survey. 
The strip is six feet in width. The north and south slopes are 
designated “A’' and respectively. Each has been subdi- 
vided into separate plats because of their somewhat individual 
characters. 
PART A. 
Plat 1 is two yards long. It is the area directly along the 
stream bank, and is made up of plants growing a part of the 
time partly submerged. 
Plat 2, three yards in length, extends from the edge of plat 
1 to the base of the hill; it has many characters in common 
with 1. 
Plat 3 extends up the talus slope for six yards to the first 
vertical cliff or rock exposure. Here, as on much of the hill- 
side above, the extreme mesophytic conditions are reflected in 
the type of plants found. 
Plat 4 is the part of the belt which extends up the cliff at 
this point. In one respect this location is not typical of the 
ledges in that here is found the Moosewood, Dirca palustris, 
which is nowhere else in this region. 
Plat 5 extends for twenty-three yards up the slope to the 
base of the next cliff, and goes up most of the way in a rock- 
strewn ravine. 
