Linum australe
Linum pratense
southern flax
blue flax, meadow flax, Norton's flax
stiffly ascending-spreading, few to many-branched.
± spreading or ascending, or branches from base prostrate.
alternate, appressed;
stipular glands present at basal nodes or throughout;
blade linear, 7–20 × 0.5–l.9 mm, margins entire, not ciliate, apex aristate.
blade linear to linear-oblanceolate, 8–20 × 0.7–2.3 mm.
racemes.
open panicles or racemes.
3–15 mm.
8–25 mm.
sepals deciduous, lanceolate to narrowly ovate, 4–7 mm, margins scarious, delicately glandular-toothed, apex aristate;
petals yellow to yellow-orange throughout, oblanceolate to narrowly obovate, 5–10 mm;
stamens (3–)4–7 mm;
anthers 0.4–1 mm;
staminodia present or absent;
styles connate nearly to apex, 2–5.7 mm;
stigmas green, capitate.
homostylous;
sepals ovate, 3–5 mm, margins glabrous, apex acute;
petals usually blue, rarely white, obovate, 5–14 mm;
stamens 3–5 mm;
anthers 0.4–1.3 mm;
staminodia present;
styles distinct, 1–3 mm;
stigmas capitate.
ovoid, 3.2–4.5 × 2.5–3.4 mm, relatively thick-walled and with characteristic thickened areas at apex in region of true septa, apex obtuse, dehiscing into 5, 2-seeded segments, segments persistent on plant, false septa complete, proximal part membranaceous, not terminating in loose fringe, distal part cartilaginous, margins ciliate.
broadly ovate to subglobose, 4–6 mm diam., apex obtuse, segments persistent on plant, margins ciliate.
2–3 × 0.8–1.3 mm.
3–5 × 1.2–1.6 mm.
= 18.
Linum australe
Linum pratense
Varieties 2 (2 in the flora).
The stems of Linum australe are strongly ridged-sulcate to ribbed, especially distally. The corollas are broadly funnelform; petals are yellow to yellow-orange; stamens and styles are yellow; stigmas are bright to olive green. Staminodia in L. australe are short, deltoid, usually two between each pair of stamens, sometimes one or absent. Linum australe is the only species in its range that is glabrous beyond the base and has connate styles. It differs from L. aristatum, which it overlaps in the southern part of the range, in being much more highly branched and having more slender capsules. C. M. Rogers (1984) noted a compact form found in sunny areas from Wyoming northward that warrants more study.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
In a study of pollination in Linum pratense, G. E. Uno (1984) observed that petals dropped soon after anthesis and the persistent sepals quickly moved inward, pressing the dehiscing anthers against the receptive stigmas. Small bees and flies were seen to visit flowers even after the petals fell. Uno noted sepals closing in both L. lewisii and L. rigidum, but in these species the stamens tend to be somewhat shorter than the styles so self-pollination was less likely.
C. M. Rogers (1984) wrote that some plants of Linum pratense intergrade with L. lewisii in areas where their ranges overlap; however, in most of its range, L. pratense is the only blue-flowered Linum, and can be distinguished from the occasional plant of L. bienne or L. usitatissimum by its lack of cilia on the inner sepals and its capitate stigmas.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Stipular glands present only at proximal nodes; stamens (3–)4–5 mm; styles (2–)2.7–3.3(–4) mm. | var. australe |
1. Stipular glands present at nodes throughout plant; stamens 5–7 mm; styles 3.6–5.7 mm. | var. glandulosum |
CalFlora
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
KS Wildflowers
