Equisetum arvense (L.) Common from Kankakee county north. Reported by
Patterson as common throughout the state. Though usually growing
in moist sand or gravel, it is often found in the Chicago region
in masses along dry railway embankments.
Equisetum palustre (L.) "Wet places. Peoria county, _Wolff_, _Brendel_."
(P.)
Equisetum fluviatile (L.) In shallow water or very wet ground. Quite
frequent about Chicago. "Cass county, _Mead_; Peoria, _Brendel_;
McHenry. _Vasey_. Scarce." (P.) Joliet, common, _Ferriss_.
Equisetum laevigatum (A. Br.) Cook and Kankakee counties. "In dry or
moist clay or sand from Henderson and Peoria counties southward."
(P.) In the Chicago region generally in moist sands; Hancock
county, _Mead_.
Equisetum hyemale (L.) Moist places. Cook, Will and Lake counties.
Frequent, as well as throughout the state according to Patterson.
Equisetum Ferrissii (Clute.) Moist banks, Will county.
Equisetum robustum (A. Br.) On moist or wet banks of streams. Thornton
and La Grange, Cook county. "River banks from Peoria county
southward." (P.)
Equisetum variegatum (Schleich.) In clayey ravines at Lake Forest and in
wet sands at Waukegan, Lake county, Peoria, _Brendel_. Var.
_Jesupi_, A. A. Eaton, and var. _Nelsoni_, A. A. Eaton, are
credited to Illinois in Gray's New Manual of Botany. The latter
variety occurs in Lake county, Ind., bordering Illinois, and is
likely to be found in the neighboring parts of this state, but
those from Lake county, Ill., agree better with the typical form.
Equisetum scirpoides (Michx.) Moist shaded ravines, Lake Bluff, Lake
county. Reported by _Cowles_ at Lake Forest. "Ringwood, McHenry
county, _Vasey_." (P.)