Monographs Details: Betula ulmoides
Authority: Hollick, Charles A. 1927. The Flora of the Saint Eugene Silts, Kootenay Valley, British Columbia. Mem. New York Bot. Gard. 7: 389-428.
Description:Species Description - Specimens represented by basal parts of leaves that resemble those of certain of our existing birches, such as the rounded or cordate forms of Betula cordifolia Eegel, B. lenta Linnaeus, B. lutea Michaux f., etc. The leaves vary in size, with rounded-truncate or subcordate, and somewhat oblique or unsymmetrical bases suggestive of the genus Ulmus, and finely dentate margins.
PLATE 31, FIGURE 1; PLATE 32, FIGURE 1
" Ulmus n. sp.?" Hollick, Summary Kept. (loc. cit.), p. 134.
A fragment originally identified as an Ulmus (loc. cit.) is represented by FIGURE I, on PLATE 31; but it appears to be more satisfactorily comparable with the genus Betula, and I have ventured to include it in that genus together with the smaller specimen represented by FIGURE 1, on PLATE 32. Satisfactory comparisons, or adequate specific description is impossible, in the absence of any knowledge in regard to the shape and the marginal characters of the upper part of the leaves. For purposes of comparison, however, I have introduced (PLATE 44, FIGURE 1) a figure of a typical average leaf of Betula lenta, the base of which is closely similar to the basilar parts of our specimens. Many individual leaves of B. lutea, however, with more conspicuously oblique bases, might also be selected for comparison, and it would be difficult to decide to which of these two species our specimens appear to bear the closest resemblance.
Betula lutea was listed from the Ottawa valley by Penhallow, 10 in a report on the Pleistocene flora of the Don Valley, Canada, but without any description or illustration.