Equisetum hyemale var. californicum Milde; A. A. Eaton, Fern Bull. 11: 113. 1903, as to the biangulate plants only.
Equisetum hiemale-vax. Doellii Milde; A. A. Eaton, Fern Bull. 11:114. 1903, Not Milde, 1863.
Typical H. hyemalis with caducous teeth has never been collected
in America. The Pacific coast plants differ in having the
teeth deciduous or more or less persistent. The plants referred
by Mr. Eaton to the var. Doellii Milde cannot belong there as that
European variety has the centrum only one fourth or one third
the diameter of the stem, while the British Columbia plants have
a centrum four fifths the diameter of the stem and the teeth are
not wholly persistent as described, at least on specimens distributed
which show them to be generally deciduous. California to