Hedeoma drummondii Complex Taxa in Mid-to-late March
by Bob Harms  email-here

[Click any image to enlarge]

H. drummondii
20 March 2013		 H. drummondii ×
H. reverchonii var. ???
30 March 2013		 H. reverchonii var. reverchonii
23 March 2013		 H. reverchonii var. serpyllifolia
17 March 2013
By mid-to-late March shoots initiated in the fall had extended, with new leaves and branches, with some plants, especially H. drummondii, having lost winter leaves from lower nodes (note the yellow arrows).

Gland Development in March

All leaves of H. drummondii, at all stages, exhibited well developed glands. H. reverchonii varieties had relatively few glands, often none were apparent on larger more recent leaves. But the very recent small leaves, on shoots arising from the upper leaf axils of H. r. var. reverchonii had well–developed glands (also center image below).

In the images below, the leftmost, with longer hairs, are from lower (winter) leaves; the rightmost are from higher, more recent leaves. The center image for H. drummondii shows glands on a winter stem, a feature not noted with either H. reverchonii variety. The dark ‘spots’ on the center image for H. r. var. serpyllifolia are the base of hairs, and their relation with gland development is unclear — there are no clear glands in that image.

H. drummondii
H. reverchonii var. reverchonii
H. reverchonii var. serpyllifolia

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