412 



Illinois Natural Histokv SuRVK'i' Bulletin 



Vol. 26, Art. 5 



tile blult-top ridge and the east-facing 

 slope of this ridge were forested, except 

 for some cleared areas serving as fields 

 for I'uitivated crops. This prairie was 

 visited on the same dates as Phegles . 



Stotz. — This hill prairie took its name 

 from a quarry about a half mile north of 

 Prairie du Rocher. Eight spurs of a bluff- 

 ridge comprised the prairie, which covered 

 about 6 acres in f^SO; intervening ravme< 

 were wooded. The southernmost s| mi 

 had been much trampled b\ humans, the 

 others pastured. Nati\e plants and weeds 

 occurred on the pastured spurs in nearU 

 equal proportions; the native plants per- 

 sisted better on the nonpastured spur than 

 on the others. .1 lulrofiot/oii scopariiis was 

 the dominant grass of the prairie slopes. 

 Patches of Huntil'iua < iirliffiiditlii grew 

 throughout tlie prairie. The orchid //c.v- 

 itlrctris spicatti was found in the wood- 

 land border at the base of one spur. Stotz 

 prairie was visited Mav 24 and Jul\ .^U, 

 l'»5(). 



Allen Lake. — A small, crescent-shaped 

 lake located near a loess-capped blui?-top 

 supplied the name for this prairie, whicli 

 was visited July 29, 1950. The prairie 

 was west of the lake and 1.2 miles south 

 of Prairie du Rocher. Prairie occupied 

 4.5 acres of the upper slope of the blul^. 

 Limestone fragments covered the lower 

 part of the slope. The dominant grass 

 was .1 nilropofiun scopiirius. 



South Prairie du Rocher. — When 

 visited June lb, 1950, this very small, 

 pastured hill prairie occupied a part of 

 the bluff 1.6 miles south of Prairie du 

 Rocher. Jndropogon scopariiis was the 

 dominant grass. Ctutilifi liihirnsa was 

 found growing in the loess. 



Grand Canyon. — In 1949, this small 

 prairie opening in section 2, T. 10 S., R. 3 

 W., 8 miles southwest of Murph\sboro, 

 Jackson County, occupied a west-facing 

 slope at the north end of the bluff called 

 Chalk Rluff, just south of the mouth of 

 the valley known as Grand Canyon. An- 

 dropogoit sioparitis was the dominant 

 grass. Small trees of hickory, sassafras, 

 and white oak were scattered throughout. 

 Grand Canyon prairie was visited Octo- 

 ber 28, 1949. 



Fountain Bluff. — This hill prairie, 

 observed in 1950 and 1951, took its name 



from the isolated upland known as Foun- 

 tain Hluff, which has a dissected loess top 

 and for the greatest part vertical sand- 

 stone walls and is situated between the 

 .Mississippi Ri\er and the broad bottoms of 

 the Hig .Mudd\ Ri\er west of the main 

 chain of bluffs in western Jackson County. 

 This isolated upland extends 4 miles 

 north and south, and is 1.8 miles across at 

 the widest part. Prairie-covered slopes 

 were observed in section 36, T. 9 S., R. 4 

 W'., at the northern end of Fountain 

 liluff, a distance of about 1 mile west and 

 a little south of Gorham. 



The northern and northwestern side 

 of Fountain Bluff is an almost vertical 

 sandstone \\all into which a sizable r;i- 

 \ine has cut southeast and then eastward 

 so that p.art of the ravine is almost paral- 

 lel to the steep northwest wall. A sizable 

 ridge lies between the ra\ine and the Mis- 

 sissippi River bottomland on the north. 

 On this ridge were the prairie-co\ered 

 slopes, described in detail below. 



.■\bove the vertical rock cliff which 

 forms the northeast wall of the ravine are 

 four rock-strewn spurs, which at the 

 time of this study were covered with prai- 

 rie plants; Andtftpogon scopariiis was the 

 dominant grass. These prairie-covered 

 spurs were separated by three narrow 

 belts of woodland in shallow drainage- 

 ways. The three narrow belts of wood- 

 land were joined upslope to form another 

 and larger belt of woodland, at right an- 

 gles to the three; the larger belt covered 

 a rock-strewn slope. 



Upslope from the rock-strewn slope, the 

 bluff is capped by loess. Three spurs on 

 this highest exposure of the ridge were 

 occupied by prairie, the intervening coves 

 by small trees and shrubs. One spur faced 

 almost westward, overlooking the Missis- 

 sippi bottomland, the others southwest- 

 ward. The westward-facing spur was 

 separated from the others by a narrow 

 belt of timber. At the ridge-top, the prai- 

 rie areas of the two southwest-facing 

 spurs were connected to form a U-shaped 

 hill prairie with the prongs of the U ex- 

 tending downslope. 



W'lien visited June 14. August 17, and 

 September 19, 1950, and April 19 and 

 May 23, 1951, prairie occupied about 3 

 acres of these spurs. 



