August. 1955 



E\ERS: Him. Prairies of Illinois 



441 



Solidago nemoralis Ait. Field golden- 

 rod was found to be the most abundant 

 goldenrod of the hill prairies. It was ob- 

 served in 33 loess and rock prairies in Illi- 

 nois. 



Solidago petiolaris Ait. This species 

 was found in cherty prairie at Tamms. 



Solidago radula Nutt. Rough golden- 

 rod was found in 15 hill prairies from 

 North Pandarmie and North Eldred 

 south to Government Rock. 



Solidago rigida L. Rigid goldenrod, 

 common in flatland prairie remnants, was 

 seen in hill prairie at El Rancho, Reavis 

 Spring, Block House, \'almeyer, Renault, 

 and Government Rock. 



Solidago speciosa Nutt. Show' gol- 

 denrod was collected from loess prairie at 

 Sunset Trail, Devil's Backbone, and Val- 

 meyer. 



Solidago tihni folia Aluhl. Elm-leaved 

 goldenrod, a plant of thickets and open 

 woods, was found in six hill prairies, 

 chiefly in stony soil. 



*Tragopogon major Jacq. \_T. dubiiis 

 Scop.] This European species was found 

 in the rock prairie at Devil's Backbone. 



*Tragopogon pratensis L. Goat's- 

 beard was found in loess prairie at Sunset 

 Trail and Oblate Fathers. 



J erbesina helianthoides Michx. This 

 crownbeard, usually found growing in 

 dry woods and thickets, was seen in rock 

 prairie at Fountain Blufif and Cave Creek 

 and in loess at Chautauqua and Fountain 

 Bluff. 



Verbesiua virginica L. ^\ hire crown- 

 beard, or tickweed, was collected from 

 rock prairie and woodland borders at 

 Cave Creek. 



Vernonia baldtiini Torr. This iron- 

 weed was found in loess at six hill prai- 

 ries from Sessions and North Eldred south 

 to Sampson. 



J'ernonia missurica Raf. More gener- 

 ally present in hill prairie than the pre- 

 ceding species, this ironweed was found in 

 11 loess hill prairies and in some of the 

 adjoining wooded coves. 



Three hundred ninety-four species and 

 varieties of plants were found by the 

 writer in the hill prairies of Illinois. Of 

 these. 390 were vascular plants distributed 

 among 209 genera and 70 families. The 

 family represented by the greatest numbers 



of species and genera was the Compositae, 

 71 species and \arieties in 26 genera. Aster 

 was the largest genus; 12 species were rep- 

 resented. The four species of nonvascular 

 plants included two species of the lichen 

 Lecidea, a liverwort, and a moss. 



Geographical Relations of the Hill 

 Prairie Flora 



The majority of plant species in Illi- 

 nois hill prairies are presumably of south- 

 eastern origin. Three of the important 

 grass species, .-indropogon scopariits. A. 

 gerardi, and Sorghastruni nutans, came 

 from southeastern United States. 



There are, however, numbers of species 

 characteristic of the western plains and of 

 the Ozark plateau. These are Bouteloua 

 hirsiita. Psoralen tenuiflora. Polytaeiiia 

 nuttallii. Asclepias sleiiophylla, Meutzelia 

 oligosperma, Salvia pitcheri, Plantago 

 purshii, Agoseris cuspidata. Ambrosia 

 eoronopifolia, Solidago drummoiidii, Aster 

 anomalus, and Rudbeckia missouriensis. 



The last three possibly are from tjie 

 Ozark plateau. In addition to the plants 

 enumerated aboxe, Synthyris biillii may 

 be mentioned as a species, possibly from 

 the Rocky Mountains, that migrated east- 

 ward along glacial moraines (Pennell 

 1935). 



SUMMARY 



1. Hill prairies are grasslands on pro- 

 nounced slopes. Prairies is here u>ed as a 

 vegetational term rather than a locational 

 or topographic term for an expansive flat. 



2. Of the many hill prairies in Illinois, 

 61, with a combined area of more than 

 200 acres, were visited by the writer in 

 the course of this study. 



3. In Illinois, hill prairies occur on 

 the exposed upper or brow slopes of the 

 generally southwest- and west-facing bluffs 

 east of the Mississippi River for most of 

 the length of the state and on similar slopes 

 along the Illinois River from Putnam 

 County southward into Jersey County, 

 where the vallc\ of the Illinois enters the 

 Mississippi vallex . Hill prairies are present 

 also along the Sangamon and Rock rivers. 



4. Location and topography exert the 

 strongest controls, or place influences, that 



