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rock flax

fairy flax, lin purgatif, purging flax, white flax

Habit Herbs, perennial, 20–75 cm, glabrous or rarely sparsely hairy proximally. Herbs, 8–30 cm, glabrous.
Stems

erect, branched at base and in inflorescence.

erect, usually unbranched proximal to inflorescence, sometimes branched from decumbent base.

Leaves

opposite near base or alternate throughout, appressed-ascending;

stipular glands present;

blade linear to linear-lanceolate, 8–20 × 0.5–2.1 mm, margins entire or with scattered minute marginal glands, not ciliate, apex acute; 1-nerved.

blade narrowly elliptic to oblanceolate or narrowly obovate or oblong, larger 5–18 × 1.4–3.1 mm, largest at midstem, reduced in size both proximally and distally, apex obtuse to acute.

Inflorescences

panicles, with ascending to spreading branches.

panicles.

Pedicels

0–3 mm.

6–35 mm.

Flowers

sepals persistent, lanceolate to ovate, 2.5–5 mm, margins of inner sepals narrowly scarious, conspicuously glandular-toothed, apex acute or acuminate;

petals lemon yellow, oblanceolate or narrowly obcordate, 7–11 mm;

stamens 2–8 mm;

anthers 0.5–1 mm;

staminodia present;

styles distinct, 3–6.5 mm;

stigmas capitate.

sepals broadly lanceolate to ovate, outer sepals 2–3 mm, inner sepals broader, shorter, margins of all or sometimes only of inner sparsely but conspicuously glandular-toothed, apex acute to acuminate;

petals white or whitish, base yellowish, 2–5 mm, obovate;

stamens 1 mm, anthers 0.2–0.3 mm;

styles 0.5–1 mm.

Capsules

ovoid, 2–3 × 2–2.5 mm, apex sharp-pointed, dehiscing readily into 10, 1-seeded segments, segments falling freely, false septa incomplete, false and true septa margins ciliate.

ovoid, 2–2.5 × 2 mm, fragile and subject to crushing when pressed;

segments persistent on plant, septa margins ciliate.

Seeds

1.2–1.9 × 0.7–1.1 mm.

1–1.5 × 0.6–0.8 mm.

2n

= 36.

= 16.

Linum rupestre

Linum catharticum

Phenology Flowering Apr–Aug. Flowering Jun–Aug.
Habitat Sandy soils, rocky slopes and ledges, often on limestone. Calcareous or sandy soils, fields, pastures, roadsides.
Elevation 150–1500 m. (500–4900 ft.) 0–400 m. (0–1300 ft.)
Distribution
from FNA
NM; TX; Mexico (Chihuahua, Coahuila, Durango, Nuevo León); Central America (Guatemala)
[WildflowerSearch map]
[BONAP county map]
from FNA
MA; ME; MI; NH; NY; PA; VT; BC; NB; NF; NS; ON; PE; QC; Europe; w Asia; Atlantic Islands (Iceland) [Introduced in North America; introduced also in South America (Argentina), Pacific Islands (New Zealand), Australia (Tasmania)]
[WildflowerSearch map]
[BONAP county map]
Discussion

Linum rupestre has narrowly funnelform corollas and yellow stamens and styles. The anthers and stigmas are held closely adjacent at the mouth of the corolla tube, below the broad, spreading limbs. The species occurs from southeastern New Mexico and central Texas to Guatemala. It often grows with L. schiedeanum in Texas and Mexico.

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

Linum catharticum has small, white, funnelform corollas, yellow anthers, and light green stigmas. It is the only Linum in the flora area with white petals and opposite leaves. The species is widespread in Europe and occurs only sporadically in the northern United States and most of its range in Canada. It may be native in Newfoundland and Nova Scotia, where it is well established.

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

Source FNA vol. 12, p. 381. FNA vol. 12, p. 377.
Parent taxa Linaceae > Linum > sect. Linopsis Linaceae > Linum > sect. Cathartolinum
Sibling taxa
L. alatum, L. allredii, L. arenicola, L. aristatum, L. australe, L. berlandieri, L. bienne, L. carteri, L. catharticum, L. compactum, L. elongatum, L. floridanum, L. grandiflorum, L. harperi, L. hudsonioides, L. imbricatum, L. intercursum, L. kingii, L. lewisii, L. lundellii, L. macrocarpum, L. medium, L. neomexicanum, L. perenne, L. pratense, L. puberulum, L. rigidum, L. schiedeanum, L. striatum, L. subteres, L. sulcatum, L. trigynum, L. usitatissimum, L. vernale, L. virginianum, L. westii
L. alatum, L. allredii, L. arenicola, L. aristatum, L. australe, L. berlandieri, L. bienne, L. carteri, L. compactum, L. elongatum, L. floridanum, L. grandiflorum, L. harperi, L. hudsonioides, L. imbricatum, L. intercursum, L. kingii, L. lewisii, L. lundellii, L. macrocarpum, L. medium, L. neomexicanum, L. perenne, L. pratense, L. puberulum, L. rigidum, L. rupestre, L. schiedeanum, L. striatum, L. subteres, L. sulcatum, L. trigynum, L. usitatissimum, L. vernale, L. virginianum, L. westii
Name authority Engelmann ex A. Gray: Boston J. Nat. Hist. 6: 232. (1850) Linnaeus: Sp. Pl. 1: 281. (1753)
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