Desmodium marilandicum |
Desmodium ochroleucum |
|||||||||
---|---|---|---|---|---|---|---|---|---|---|
Maryland tickclover, smooth small-leaf tick-trefoil |
cream ticktrefoil |
|||||||||
Habit | Herbs, perennial. | Herbs, perennial. | ||||||||
Stems | ascending to erect, usually striate, branched or unbranched, 30–150 cm, glabrous or sparsely to densely uncinate-puberulent, sometimes also patent long-pilose. |
decumbent or prostrate, 50–100 cm, patent-villous and uncinate-puberulent. |
||||||||
Leaves | trifoliolate; stipules caducous or moderately persistent, subulate to narrowly ovate, 2–5 mm; petiole 1–30 mm; leaflet blades narrowly ovate, elliptic, elliptic-ovate, ovate-rhombic, or suborbiculate, apex obtuse or acute, mucronulate, surfaces sparsely to densely uncinate-puberulent and appressed-villous abaxially, uncinate-puberulent or glabrescent adaxially; terminal blade 9–75 × 6–33 mm, length 1.5–4(–5) times width. |
usually trifoliolate, rarely unifoliolate; stipules persistent, reflexed in age, deltate or ovate, 5–12 mm, base obliquely cordate, subamplexicaul; petiole 10–35 mm; leaflet blades ovate, ± leathery, apex obtuse or sometimes acute, surfaces prominently reticulate-veined adaxially, uncinate-puberulent on veins or glabrescent abaxially, uncinate-puberulent adaxially; terminal blade 30–75 × 22–53 mm, length 1.2–2 times width. |
||||||||
Inflorescences | terminal and branched, axillary and unbranched; rachis uncinate-puberulent; primary bracts ovate, 1.5–3 mm. |
ascending to erect, axillary distally and unbranched, sometimes also terminal and branched; rachis pilose and uncinate-puberulent; primary bracts caducous, broadly ovate, 5–6 mm. |
||||||||
Pedicels | 3–19 mm, uncinate-puberulent. |
10–20 mm. |
||||||||
Flowers | calyx 1.5–2.5 mm, pubescent (not uncinate-puberulent), tube 1 mm; abaxial lobes 1.2–1.5 mm, lateral lobes 1 mm; corolla usually lavender to red-violet or pink-purple, rarely white, 4–6 mm. |
calyx 3–4 mm, pilose and uncinate-puberulent, tube 1 mm; abaxial lobes 3 mm, lateral lobes 1.2–1.5 mm, to 2.5 mm in fruit; corolla white or ochroleucous, 7–8 mm. |
||||||||
Loments | sutures crenate abaxially, sinuate adaxially; connections adaxial, 1/4–1/2 as broad as segments; segments 1–4, broadly elliptic, 3.5–5.5 × 2.5–4 mm, rounded abaxially, convex adaxially, uncinate-puberulent throughout; stipe 1–2 mm. |
sutures deeply crenate abaxially, crenate adaxially, contorted by irregular folding of margins near or at connection between segments; connections adaxial, 1/5–1/4 as broad as segments; segments 3–5, suborbiculate to subrhombic, 7–10 × 5–8 mm, symmetrically rounded abaxially, convex adaxially, glabrous, sutures uncinate-pubescent; stipe 0 mm (or indistinctly stipitate by narrowing proximal segment). |
||||||||
2n | = 22. |
|||||||||
Desmodium marilandicum |
Desmodium ochroleucum |
|||||||||
Phenology | Flowering summer–fall. | |||||||||
Habitat | Open woodland, roadsides. | |||||||||
Elevation | 30–500 m. (100–1600 ft.) | |||||||||
Distribution |
e United States; sc United States; West Indies
|
AL; DC; DE; FL; GA; MD; MO; MS; NC; NJ; TN; VA |
||||||||
Discussion | Varieties 3 (3 in the flora). Desmodium ciliare, D. lancifolium, and D. marilandicum have generally been recognized as closely related but distinct species in floras of the United States. They commonly have two or three articulate, small loments. D. Isely (1990, 1998) grouped them as the D. ciliare Group and regarded forms intermediate between them as putative hybrids: D. ciliare × D. marilandicum and D. ciliare × D. lancifolium. They have been separated by differences in the leaflets and pubescence, but the differences are not always clear. They are treated here as one species with three varieties. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The range of Desmodium ochroleucum is highly fragmented, and only about a dozen populations are known. Fire suppression may have been responsible for closing the canopy in forests in which D. ochroleucum is usually found (R. W. Tyndall and P. L. Groller 2006). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||||||
Key |
|
|||||||||
Source | FNA vol. 11. | FNA vol. 11. | ||||||||
Parent taxa | ||||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Synonyms | Hedysarum marilandicum, Meibomia marilandica | Meibomia ochroleuca | ||||||||
Name authority | (Linnaeus) de Candolle in A. P. de Candolle and A. L. P. P. de Candolle: Prodr. 2: 328. (1825) — (as marylandicum) | M. A. Curtis ex Canby: Proc. Acad. Nat. Sci. Philadelphia 16: 17. (1864) | ||||||||
Web links |