THE VEGETATION OF SKOKIE MARSH, WITH SPECIAL 
REFERENCE TO SUBTERRANEAN ORGANS AND 
THEIR INTERRELATIONSHIPS 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 155 
Ear E. SHERFF 
(WITH TEN FIGURES) 
The work on which this paper is based was begun in the autumn 
of 1910 and was concluded in the autumn of ro11. The detailed 
study of subterranean organs was carried on chiefly in the summer 
of 1911. The writer gratefully acknowledges his indebtedness for 
many valuable suggestions and much helpful advice, to Dr. HENRY 
C. Cowes and to Mr. Greorce D. FULLER, under whose joint 
supervision the investigation was pursued, and also to Dr. J. M. 
GREENMAN for certain taxonomic assistance. 
Skokie Marsh’ is intimately associated with Skokie Stream, a 
small, sluggish stream beginning west of Waukegan, IIl., and extend- 
ing southeast to a point west of Glencoe, Ill. Because of inter- 
ference by cultivation and by drainage, the areal limits of the marsh 
can be defined only arbitrarily. As shown in the accompanying 
map (fig. 1), however, Skokie Marsh is approximately 12 km. long 
and at its southern end becomes 1.5 km. wide. 
In early postglacial times, the marsh was an embayment 
(Atwoop and Go.tpTHwalrT I, p. 58), which later subsided, giving 
place to a system of drainage. At present the surface soil almost 
throughout the marsh consists of a black muck or partially decayed 
peat, 1 m. or less in thickness. Underneath is a subsoil of glacial 
clay. 
General features of the marsh vegetation 
* Upon analysis, the vegetation at Skokie Marsh is found to con- 
sist of three rather pronounced formations. Along the course 
' For many additional data and photographs of Skokie Marsh, see BAKER (2). 
words “formation” and “association” are used throughout this paper in 
the sense accepted by WARMING (16). 
415] [Botanical Gazette, vol. 53 
