Pityopsis aspera |
Pityopsis graminifolia |
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pineland silkgrass |
grass-leaf goldenaster, narrowleaf silkgrass |
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Habit | Perennials, 20–50 cm; rhizomes 1–20 cm. | Perennials, 20–80 cm; rhizomes 3–20 cm. | ||||||||||||||||||||
Stems | usually 1, erect, green to brown distally, simple, slender, proximally silky-sericeous, distal 2/3 sometimes densely stipitate-glandular. |
1–5+, erect, green to brown beneath hairs, simple, silvery-sericeous (hairs irregularly anastomosing-cohering). |
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Leaves | basal overwintering, in rosettes (at ends of short rhizomes), ascending to spreading, blades linear-oblanceolate, 50–250(–350) × 5–10 mm, margins sometimes stipitate-glandular, apices acute, faces sparsely to densely silky-sericeous; cauline ascending, linear, greatly reduced distally, margins sparsely to densely stipitate-glandular, sparsely sericeous, glabrescent, or densely stipitate-glandular; proximal 30–120 × 2–10 mm, distal 20–50 × 1–3 mm, sometimes glabrate. |
basal sessile, blades linear to lanceolate, grasslike, longer or shorter than cauline, 80–250(–400) × 2–20 mm, faces densely silvery-sericeous (hairs irregularly anastomosing-cohering); cauline 20–60, sometimes crowded, spreading to ascending, linear or lanceolate to ovate, usually reduced distally, apices acute, faces silvery-sericeous; distalmost sometimes greatly reduced. |
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Peduncles | 1–7, 1–6 cm, densely stipitate-glandular, glabrescent; bracteoles linear, stipitate-glandular. |
1–10 cm, sericeous; bracts and bracteoles 3–20, appressed, often grading into phyllaries. |
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Involucres | turbinate, 4.5–8 mm (shorter than mature pappi). |
turbino-campanulate, 5–13 mm (usually shorter than pappi). |
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Ray florets | 6–10; laminae 4–6 mm. |
9–13; laminae 4–14 mm. |
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Disc florets | 15–45; corollas 4–5.5 mm, proximal throats glabrate to sparsely short-pilose, lobes 0.5 mm, glabrous to sparsely pilose. |
15–50; corollas 4–9 mm, limb bases glabrate to sparsely pilose or rarely limbs moderately long-pilose; lobes 0.5–0.8 mm, glabrous to sparsely pilose. |
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Phyllaries | in 5–7 series, margins fimbriate, sparsely piloso-ciliate, moderately so distally (green zones in distal 1/2), apices acute, sometimes long piloso-ciliate distally, faces moderately stipitate-glandular. |
in 4–6 series, margins fimbriate, piloso-ciliate, faces sparsely to moderately pilose (hairs often twisted), often more densely so distally, sometimes stipitate-glandular. |
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Heads | (4–)10–79, in corymbiform arrays. |
(2–)10–100+, in corymbiform to sometimes paniculiform arrays. |
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Cypselae | fusiform, 2–3 mm, ribbed, faces strigose; pappi: outer of linear to linear-triangular scales 0.5–1 mm, inner of 25–35 bristles 5–6 mm. |
fusiform, 2.5–4.5 mm, strigose; pappi: outer scales 0.4–0.9 mm, inner 25–45 bristles 5–9 mm. |
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Pityopsis aspera |
Pityopsis graminifolia |
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Distribution |
AL; FL; GA; LA; MS; NC; SC; VA
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AL; AR; DE; FL; GA; KY; LA; MD; MS; NC; OH; OK; SC; TN; TX; VA; se Mexico; Bahamas; Central America (Belize, Guatemala, Honduras)
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Discussion | Varieties 2 (2 in the flora). Pityopsis aspera grows on the outer coastal plain. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 5 (5 in the flora). The varieties can be difficult to distinguish in this highly variable species. The infraspecific classification presented by J. C. Semple and F. D. Bowers (1985) is followed here. Involucre height increases somewhat with age, making assignment of post flowering specimens of var. tenuifolia (diploid), var. latifolia (tetraploid), and var. tracyi (hexaploid) more difficult. Data on the distribution of diploids, tetraploids, and hexaploids (Semple and Bowers 1987; subsequent reports) indicate that only diploids occur west of the Mississippi River, while only tetraploids are known in the more northern parts of the range (n Alabama, Tennessee, North Carolina, Virginia). All three ploidy levels occur in Florida, where the three varieties are most distinct. Ploidy level correlates with involucre height in the limited sample of cytovouchers. Additional study is needed to sort out more fully biogeographic patterns of variation in the tenuifolia-latifolia-tracyi complex of Pityopsis graminifolia. An alternative treatment would be to combine all three in a single variety including a polyploid series, under the name var. tenuifolia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 225. | FNA vol. 20, p. 225. | ||||||||||||||||||||
Parent taxa | Asteraceae > tribe Astereae > Pityopsis | Asteraceae > tribe Astereae > Pityopsis | ||||||||||||||||||||
Sibling taxa | ||||||||||||||||||||||
Subordinate taxa | ||||||||||||||||||||||
Synonyms | Chrysopsis graminifolia var. aspera, Chrysopsis aspera, Heterotheca aspera | Inula graminifolia, Chrysopsis graminifolia, Heterotheca graminifolia | ||||||||||||||||||||
Name authority | (A. Gray) Small: Man. S.E. Fl., 1341. (1933) | (Michaux) Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 318. (1840) | ||||||||||||||||||||
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