Service has constructed a lookout tower. The eleva- 
tion at this site is 740 feet; from the tower a view of 
the ridges and bottomland is obtained, fig. 27. 
The ridges support a mixed forest, including such 
species as chinquapin oak, northern red oak, black 
oak, sweet gum, bitternut hickory, tulip tree, and red 
cedar. Hop hornbeam, Hercules’ club, and redbud grow 
as understory trees. Poison ivy, smooth sumac, and 
winged sumac are common shrubs. In some places two 
species of greenbrier form dense, almost impenetrable 
patches. Plume grass grows profusely in some of the 
small openings of the ridge top and also on some 
slopes. 
The ravine slopes support a forest that includes 
some of the species enumerated above and also beech 
and tulip tree, which are very abundant. The under- 
story includes flowering dogwood, papaw, and, along 
the rivulets, the blue beech. On these slopes the 
Christmas, the maidenhair, the broad beach, the glade, 
and other ferns are not uncommon. In spring, numerous 
wild flowers clothe the slopes. 
When I visited this area in 1949, a small hill 
prairie occupied part of the west-facing brow slope 
at the northern extremity of Chalk Bluff. Little blue- 
stem was the dominant grass. Scattered throughout 
the prairie were small hickories, sassafras, and 
white oak (Evers 1955). 
The bottomland forest beyond Chalk Bluff toward 
the Big Muddy River contains such species as over- 
cup oak, swamp white oak, pin oak, pecan, and big 
shellbark hickory. 
Grand Canyon harbors some rare and semirare 
plant species: the clubmoss Lycopodium lucidulum, 
which grows on a sandstone cliff of one of the tribu- 
tary ravines (Evers 1950); sphagnum moss, which 
covers a sizable, moist sandstone outcrop in another 
ravine; and several orchids, including Wister’s coral- 
root and twayblade. 
Fig. 27.—- Deciduous forest as seen from Hickory 
Ridge Lookout Tower in the Grand Canyon area. 
: Fig. 28.-- Cherty limestone cliff on the bluffs of the 
Mississippi River at Pine Hills. This cliff rises to a height 
of 100 feet above the nearby bottomland. 
Much of Grand Canyon natural area is under the 
supervision of the United States Forest Service, but 
some parts remain in private ownership. 
16. PINE HILLS AND WOLF LAKE 
One of the most beautiful localities in Illinois 
is Pine Hills and the adjacent Wolf Lake and Larue 
swamps in Union County. No matter what the season 
is -- winter, spring, summer, or autumn -- this place 
abounds in natural beauty. It is located in sections 
5a De LOre lS, 1G e210. 226 27, 285 33 and 34; Tn 11 
S., R. 3 W., and sections 3 and 4, T. 12S., R. 3 W. 
The hills extend 6 miles north from the village of 
Wolf Lake. 
The bluffs of the Mississippi River that form 
Pine Hills are underlain with cherty limestone that 
outcrops to form sizable cliffs up to 100 feet high, 
fig. 28. Cherty slopes lie above the cliffs, and loess 
caps the bluffs. At the cliff bases, toe slopes of var- 
ious sizes have been formed of rock fragments that 
have spalled from the cliff faces. The swamps are in 
the bottomland adjacent to the bluffs, fig. 29. They 
occupy the old channel of the Big Muddy River, which 
enters the Mississippi River valley west of Murphys- 
21 
