Hedeoma drummondii Complex Plants, March 27/April 6
by Bob Harms ()
Early spring growth continued to show clear differences among the 3 taxa of H. drummondii. The photos on this page were taken on March 27 (side views) and April 6 (top views) of plants in N. Hays Co., both wild and in large pots with full exposure to sun and weather.
[Click on any image for enlargement.]
H. drummondii — 2 plants
Transplanted as very small plants from (1) a W. Travis Co. roadside in December (top row) and (2) a ranch just E. of Dripping Springs in Hays Co. in late January (second row). Both plants exhibit vigorous branching in the upper stems, with loss of winter leaves at the base. All leaves are narrow with abundant glands, strongly scented.
H. reverchonii var. reverchonii — 2 plants
Transplanted as very small plants from the Shield Ranch in W. Travis Co. More branched at the base than above, with leaves more broadly elliptic than H. drummondii (above) but less so than H. r. var. serpyllifolia (below). Gland development is between that of the other two taxa.
H. reverchonii var. serpyllifolia — 2 plants
Both plants are from the Keyes Ranch in W. Hays Co. The top row plant was transplanted in November; the bottom row large plant is on a caliche hillside shelf. Branching is mostly at the base, with shoots preserving early winter leaves. New leaves are very broadly elliptic, with only weakly developed glands (and very little scent). In its winter/early spring habit this taxon is more distinct from H. drummondii than H. r. var. reverchonii.
H. drummondii × H. reverchonii hybrid
Transplanted as a small plant from a ranch just E. of Dripping Springs in Hays Co. in late January. When collected it had broadly ovate leaves and did not produce a clear scent in the field. Later, by crushing several leaves, I was able to detect a weak camphor scent — so I assumed it was H. r. var. serpyllifolia. In preparing this presentation it seemed to me that the spring plant did not match the habit of any of the 3 taxa. I again test the scent and this time I sensed both lemon and mint, although not the sharp peppermint of H. drummondii. A colleague tested it and perceived both 'minty' (by just touching the leaves) and camphor, although somehow different when retested 5 hours later. The lower leaves are similar to those of H. r. var. serpyllifolia, but the top leaves are narrow like those of H. drummondii. The ranch is in an area from which R. Irving had collected hybrids for his research, so I am led to conclude this plant is a hybrid of
H. drummondii × H. reverchonii, variety uncertain at present.
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