Xyris baldwiniana |
Xyris ambigua |
|
---|---|---|
Baldwin's yelloweyed grass |
coastal plain yelloweyed grass |
|
Habit | Herbs, perennial, densely cespitose, 15–40(–50) cm. | Herbs, perennial, cespitose or solitary, 30–100 cm. |
Leaves | erect or ascending, 10–30 cm; sheaths glossy light brown or red-brown, firm; blade green, linear to filiform, often angularly terete, or sulcate, rarely to 1mm wide. |
in broad or narrow fans, (5–)10–40(–50) cm; sheath base tan, straw-colored, or pale pink; blade pale or olive green, linear-triangular, (2–)3–7(–10) mm wide, smooth or slightly papillate, margins smooth to minutely scabrous or papillate. |
Inflorescences | scape sheaths exceeded by leaves; scapes linear, straight or flexuous, terete, 1 mm wide, rarely 1-ribbed; spikes ovoid to ellipsoid, 4–7 mm, apex acute; fertile bracts 4–5 mm, margins entire or erose, apex rounded. |
scape sheaths much exceeded by leaves; scapes linear, rarely flexuous, terete or nearly terete, 1–1.5 mm wide, distally usually 2-ribbed, sometimes with additional ribs; spikes ovoid to ellipsoid, lanceoloid, or cylindric, 10–20(–30) mm; fertile bracts 5–8 mm, margins entire, apex rounded. |
Flowers | lateral sepals included, reddish brown, slightly curved, less than 5 mm, keel scarious, lacerate from middle to tip; petals unfolding in morning, blade obovate, to 5 mm; staminodes beardless. |
lateral sepals included, dark brown, strongly curved, 4–7 mm, keel firm, ciliate, petals unfolding in morning, blade obovate, 10 mm; staminodes bearded. |
Seeds | translucent, fusiform to cylindric, (0.7–)0.8–1 mm, finely lined longitudinally. |
translucent, ovoid to ellipsoid, 0.5–0.6 mm, finely multiribbed and cross ribbed. |
2n | = 18. |
= 18. |
Xyris baldwiniana |
Xyris ambigua |
|
Phenology | Flowering late spring–fall. | Flowering late spring–fall (all year south). |
Habitat | Moist to wet sands, sandy peats of bogs, pine savanna, ditches and low cleared areas, coastal plain | Acid, sandy, moist pine or oak savanna, pine flatwoods, pond shores, ditches, bogs |
Elevation | 0–200 m (0–700 ft) | 0–300 m (0–1000 ft) |
Distribution |
AL; AR; FL; GA; LA; MS; NC; SC; TX; Mexico (Chiapas); Central America (Belize, Honduras, Nicaragua)
|
AL; AR; FL; GA; LA; MS; NC; SC; TN; TX; VA; Mexico; Mexico; West Indies (Cuba); Central America (Belize, Honduras, Nicaragua)
|
Discussion | The beardless staminodes and the long, translucent seeds distinguish Xyris baldwiniana. Its leaf blades vary from terete to flat, and in eastern Texas and North Carolina the flat-leaved ones have been mistaken for X. elliottii. This same problem exists in Floridian narrow-leaved X. elliottii, which bears a strong resemblance to X. baldwiniana but has bearded staminodes and larger spikes. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Xyris ambigua is one of the more widespread and weedy of xyrids, frequently invading disturbed moist, sandy areas. It is also one of the most variable in habit and apparently forms intermediates with X. stricta and X. torta. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 22. | FNA vol. 22. |
Parent taxa | Xyridaceae > Xyris | Xyridaceae > Xyris |
Sibling taxa | ||
Synonyms | X. baldwiniana var. tenuifolia, X. juncea, X. setacea | |
Name authority | Schultes: in J. A. Schultes and J. H. Schultes, Mant. 1: 351. (1822) | Beyrich ex Kunth: Enum. Pl. 4: 13. (1843) |
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