Crepis tectorum |
Crepis capillaris |
|
---|---|---|
annual hawksbeard, crépis des troits, narrow-leaf hawk's-beard, rooftop hawksbeard |
crépis capillaire, smooth hawk's-beard |
|
Habit | Annuals, 10–100 cm (taproots shallow). | Annuals or biennials, 10–90 cm (taproots shallow). |
Stems | 1, erect (fistulose), branched distally or from bases, tomentulose and/or hispid. |
1(–6+), erect to ± procumbent, usually simple (usually with single stout leader, sometimes multiple with slender laterals), hispid proximally or throughout. |
Leaves | basal and cauline; petiolate; blades lanceolate to oblanceolate, often coarsely runcinate, 5–15 × 1–4 cm, margins entire, denticulate, or dentate to pinnately lobed (lobes remote, coarse, unequal), apices acute to acuminate, abaxial faces glabrous or tomentose, adaxial glabrous (proximal cauline sessile, bases auriculate, distal usually linear, entire). |
basal and cauline; petiolate (petiole bases clasping); blades lanceolate or oblanceolate, runcinate or lyrate, 5–30 × 1–4.5 cm, margins pinnately divided to sharply dentate (lobes remote, unequal), apices obtuse or acute, mucronate, faces glabrous or sparsely hispid (hairs yellow; proximal cauline auriculate and clasping). |
Involucres | cylindro-campanulate, 6–9 × 7–8 mm. |
cylindric to turbinate, 5–8 × 3–6 mm. |
Florets | 30–70; corollas yellow (without red on ligules), 10–13 mm. |
20–60; corollas deep yellow (reddish abaxially), 8–12 mm (hairy). |
Phyllaries | 12–15, lanceolate, 5–9 mm, (bases becoming keeled and thickened, margins scarious), apices acute to attenuate (white-ciliate, tomentulose), abaxial faces tomentose to hispidulous, adaxial with fine, appressed hairs. |
8–16, lanceolate, 6–7 mm (margins scarious), apices acute, abaxial faces stipitate-glandular and glandular setose (setae black, usually in 2 rows), adaxial glabrous. |
Calyculi | of ± 12, subulate, tomentose and hispidulous bractlets 2–5 mm (often becoming scarious). |
of 8, linear, tomentulose or stipitate-glandular bractlets 2–4 mm. |
Heads | 5–20(–100+), in paniculiform or corymbiform arrays. |
10–15(–30+), in corymbiform arrays. |
Cypselae | dark reddish or purplish brown, fusiform, 3–4 mm, apices constricted (not beaked), ribs 10 (rounded, minutely spiculate); pappi white (fine, soft), 4–5 mm. |
brownish yellow, fusiform, 1.5–2.5 mm, apices narrowed (not beaked), ribs 10 (glabrous or scabrous); pappi white (fluffy), 3–4 mm (scarcely surpassing phyllaries). |
2n | = 8. |
= 6. |
Crepis tectorum |
Crepis capillaris |
|
Phenology | Flowering May–Sep. | Flowering May–Nov. |
Habitat | Dry, sandy, pine woods, disturbed places, abandoned fields, forest clearings, wooded slopes, dry streambeds | Meadows, pastures, lawns, roadsides, fields, waste places |
Elevation | 100–300 m (300–1000 ft) | 0–1300 m (0–4300 ft) |
Distribution |
AK; CA; CT; DC; IA; IL; IN; MA; MD; ME; MI; MN; MO; MT; NC; ND; NE; NJ; NY; OH; OR; PA; RI; WA; WI; WY; AB; BC; LB; MB; NB; NS; NT; ON; QC; SK; YT; Greenland; Europe [Introduced in North America; introduced, Asia]
|
AK; AR; CA; CO; CT; DC; DE; IA; ID; IL; IN; KY; MA; MD; ME; MI; MO; MS; MT; NC; ND; NH; NJ; NV; NY; OH; OR; PA; RI; TN; TX; UT; VA; VT; WA; WI; WV; AB; BC; NB; NS; ON; QC; Europe [Introduced in North America]
|
Discussion | Crepis tectorum is recognized by its annual habit, keeled phyllaries with minute hairs on adaxial faces, and dark reddish or purplish brown cypselae. It is widespread, often abundant, occurs in a great variety of habitats, and is considered a noxious weed in some states. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Crepis capillaris is recognized by its shallow root system, dense rosettes of coarsely dentate or pinnately lobed leaves, erect slender stems, auriculate-based cauline leaves, relatively small heads, phyllaries with double rows of black setae, and fluffy white pappi. It is weedy and can become a serious lawn pest. It is one of only three species of Crepis with 2n = 6; E. B. Babcock (1947) considered it to be advanced in the genus. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 19, p. 238. | FNA vol. 19, p. 228. |
Parent taxa | Asteraceae > tribe Cichorieae > Crepis | Asteraceae > tribe Cichorieae > Crepis |
Sibling taxa | ||
Synonyms | Lapsana capillaris, C. cooperi, C. virens | |
Name authority | Linnaeus: Sp. Pl. 2: 807. (1753) | (Linnaeus) Wallroth: Linnaea 14: 657. (1840) |
Web links |
|
|