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green threads, Hopi tea, Hopi tea greenthread, rayless greenthread

hairy greenthread, Navajo tea

Edwards Plateau greenthread, slender greenthread

Habit Perennials or subshrubs, (20–)30–80+ cm. Perennials, 10–30(–40+) cm (caudices often woody). Perennials or subshrubs (may flower first year), (20–)30–70+ cm.
Cauline leaves

± scattered over proximal 1/2–3/4 of plant heights, internodes mostly 40–100 mm;

lobes mostly linear to filiform, sometimes oblanceolate, 20–40(–50+) × 0.5–1(–2.5) mm.

mostly crowded over proximal 1/4(–1/2) of plant heights, internodes mostly 1–5(–35 mm);

lobes mostly oblanceolate to linear, (5–)10–35(–45+) × (1–)2–3(–5) mm.

± scattered over proximal 3/4+ of plant heights, internodes mostly 45–95 mm;

lobes mostly linear to filiform, sometimes oblanceolate, (5–)15–45(–60) × 0.5–1(–2) mm.

Ray florets

0.

0, or 8;

laminae yellow, (6–)12–20+ mm.

usually 8, rarely 0;

laminae yellow, 9–15(–20+) mm.

Disc corollas

yellow, often with red-brown nerves, throats shorter than lobes.

yellow, sometimes with red-brown nerves, throats equal to or longer than lobes.

yellow with red-brown nerves, throats equal to or longer than lobes.

Calyculi

of 3–5+ ovate to oblong bractlets 1–2(–3) mm.

of 7–9 deltate to lance-linear bractlets 2–4+ mm.

of 6–8+ linear to subulate bractlets 1–3+ mm.

Cypselae

5–8 mm;

pappi 1–2(–3) mm.

5–7 mm;

pappi usually 0, rarely 0.1–0.5 mm.

3–4 mm;

pappi usually 0, rarely 0.1–0.3+ mm.

2n

= 22, 44.

= 22, 24.

= 20.

Thelesperma megapotamicum

Thelesperma subnudum

Thelesperma simplicifolium

Phenology Flowering (Apr–)May–Oct. Flowering May–Sep. Flowering Apr–Jul(–Oct).
Habitat Disturbed places on sands or clays, oak/juniper woodlands, desert scrub, yellow-pine forests Openings in pinyon/juniper or yellow-pine forests, often on talus or "balds" Openings in oak/juniper woodlands or desert scrub, usually on limestone
Elevation 300–2900 m (1000–9500 ft) 1000–2900 m (3300–9500 ft) 100–1500 m (300–4900 ft)
Distribution
from FNA
AR; AZ; CO; KS; NE; NM; OK; SD; TX; UT; WY; South America; Mexico (Chihuahua, Coahuila)
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; MT; ND; NM; NV; UT; WY; AB
[WildflowerSearch map]
[BONAP county map]
from FNA
TX; Mexico (Chihuahua, Coahuila, Nuevo León, Tamaulipas)
[WildflowerSearch map]
[BONAP county map]
Discussion

Thelesperma megapotamicum sometimes persists after plantings outside its natural range in the flora area and may become established (e.g., in California).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

As here circumscribed, Thelesperma subnudum includes plants that have been treated as distinct species and/or varieties (some of which have been treated as of conservation concern). See C. J. Hansen et al. (2002) for an alternate interpretation of T. subnudum.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Thelesperma simplicifolium is used in roadside plantings and may be encountered as a waif outside its natural range in the flora area (e.g., in California).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 21, p. 202. FNA vol. 21, p. 201. FNA vol. 21, p. 201.
Parent taxa Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Thelesperma Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Thelesperma Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Thelesperma
Sibling taxa
T. ambiguum, T. burridgeanum, T. filifolium, T. flavodiscum, T. longipes, T. nuecense, T. simplicifolium, T. subnudum
T. ambiguum, T. burridgeanum, T. filifolium, T. flavodiscum, T. longipes, T. megapotamicum, T. nuecense, T. simplicifolium
T. ambiguum, T. burridgeanum, T. filifolium, T. flavodiscum, T. longipes, T. megapotamicum, T. nuecense, T. subnudum
Synonyms Bidens megapotamica, T. gracile T. caespitosum, T. marginatum, T. pubescens, T. pubescens var. caespitosum, T. subnudum var. alpinum, T. subnudum var. marginatum, T. subnudum var. pubescens, T. windhamii Cosmidium simplicifolium, T. curvicarpum
Name authority (Sprengel) Kuntze: Revis. Gen. Pl. 3(2): 182. (1898) A. Gray: Proc. Amer. Acad. Arts 10: 72. (1874) (A. Gray) A. Gray: Hooker’s J. Bot. Kew Gard. Misc. 1: 252. (1849)
Web links 
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