The native vegetation of the refuge can be clas- 
sified as (1) forest and (2) aquatic and semiaquatic. 
On the island and on some of the land to the west of 
the central arm are cultivated fields of corn, sun- 
flowers, and soybeans. The products of these fields 
serve as food for the Canada geese that come here in 
huge numbers in October and remain until March. 
Floating on or just beneath the surface of the 
lake, sometimes densely covering immense areas, are 
several duckweeds, including the rare Wolffiella flori- 
dana. The mosquito fern floats in such numbers on 
the water, either with the duckweeds or in pure 
stands, that the surface of some parts of the lake is 
completely covered, fig. 30, and assumes a purplish 
hue. Hornwort and other aquatic plants grow sub- 
merged in the lake. Bald cypress and tupelo rise from 
the shallow water to produce the picturesque appear- 
ance of Horseshoe Lake, fig. 31. In small, shallow 
pools of the west am, American lotus covers large 
areas. The vast numbers of large, circular leaves rise 
from the water to heights of 6 feet. In July and Au- 
gust, thousands of cream-colored flowers, 6 inches or 
more across, appear over the leafy mass. 
In the very shallow water along the shore, such 
plants as arrowhead, pickerel weed, and primrose- 
willow are frequently observed. Other plants of the 
fluctuating shoreline are buttonbush, swamp privet, 
swamp honey locust, swamp cottonwood, Drummond’s 
maple, box elder, and numerous herbs, including 
Eclipta alba. 
On slightly higher ground bordering the lake 
shore, other tree species grow in profusion. Shingle, 
pin, swamp white, overcup, and southern red are the 
most common of the species of oaks. Soft maple is 
common; basswood is scattered here and there, as are 
black walnut and pecan. Three vines are common on 
trunks of the trees: Virginia creeper, trumpet creeper, 
and poison ivy. Two additional vines, raccoon grape 
and passion flower, are less common but can be easily 
found. In the plant community bordering the lake, 
clearweed, false nettle, and water horehound are 
abundant. 
Numerous picnic tables have been placed near 
the lake and close to some of the all-weather roads. 
The island is usually closed to the public. The over- 
wintering geese attract to this area numerous hunters 
and bird watchers who, it is estimated, spend over a 
million dollars annually in Cairo and the vicinity. 
Horseshoe Lake Wildlife Refuge is under the 
supervision and control of the State of Illinois De- 
partment of Conservation. 
18. CACHE RIVER SWAMPS 
Remnants of once vast cypress swamps are found 
in a number of localities in southern [llinois, includ- 
ing the Cache River valley and the broad valley that 
Fig. 31.-- Bald cypress and tupelo growing in the water of Horseshoe Lake, Alexander County. Primrose-willow also 
grows in the water here (foreground). 
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