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Alaska piperia, slender-spire orchid

Michael's piperia, Michael's rein-orchid

Habit Plants 9–70 cm. Plants 9–70 cm.
Stems

swollen to uniform diameter toward base, 0.7–6.1 mm diam. distal to leaves;

bracts 1–8.

attenuate toward tuberoid, fistulous, 1.5–12(–17) mm diam. distal to leaves;

bracts 3–50.

Leaves

prostrate;

blade 5–16(–20) × 1.3–3.5 cm.

prostrate to erect-spreading;

blade 7–22(–30) × 1.5–4(–6.2) cm.

Inflorescences

usually sparsely flowered, 3–44 cm;

rachis usually longer than peduncle;

bracts 3–23 mm.

± densely flowered, 3–33 cm;

rachis usually shorter than peduncle;

bracts 4–17(–22) mm.

Flowers

± translucent green, fragrance nocturnal but lingering during day, musky or soapy, sometimes honeylike;

sepals ± translucent, 2–4.2 × 1–2.6 mm;

dorsal sepal ovate to oblong;

lateral sepals spreading to strongly recurved;

petals usually projecting to erect, ± straight-sided, asymmetrically ovate to linear-lanceolate, 2–5.5 × 0.6–2 mm;

lip ± deflexed, broadly ovate to lanceolate-elliptic, 2–5 × 1–3 mm, apex usually somewhat upcurved;

spur horizontal to decurved, 2–5.5 mm, ± equal to lip;

viscidia broadly elliptic-ovate, 0.15–0.5 × 0.1–0.3 mm;

rostellum blunt.

green, fragrance nocturnal, strong, pleasant;

sepals 2–4.8 × 1.3–3.7 mm;

dorsal sepal ovate-elliptic to ovate;

lateral sepals spreading to recurved, oblong-lanceolate to oblong-ovate;

petals erect-spreading, asymmetrically triangular-ovate, 2.2–4.5 × 1–2.2 mm;

lip straight to ± bent, ovate-triangular, 1.7–5 × 1.3–5 mm;

spurs mostly deflexed, sometimes mixed with horizontal ones, 9–16 mm;

viscidia broadly oblong, 0.4–0.75 × 0.15–0.4 mm;

rostellum blunt.

Capsules

3.5–10.5 mm.

5–13 mm.

Seeds

tan to cinnamon brown.

blackish brown, rarely brown.

Piperia unalascensis

Piperia michaelii

Phenology Flowering Jun–Aug; Apr–May, lowlands of n Calif. Flowering late Apr–mid Aug.
Habitat Coniferous and mixed evergreen forests, generally dry sites, rarely coastal bluffs Coastal bluffs and scrub, chaparral, oak woodland
Elevation 0–3000 m (0–9800 ft) 0–700 m (0–2300 ft)
Distribution
from FNA
AK; CA; CO; ID; MI; MT; NM; NV; OR; SD; UT; WA; WY; AB; BC; NF; ON; QC
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[WildflowerSearch map]
Discussion

The racemes in Piperia unalascensis are usually slender and sparsely flowered; racemes of uncommon coastal populations (including the type) are short, stout, and densely flowered. Plants of the coast ranges and the Pacific Northwest are stouter and have broader sepals and petals than do interior and montane forms. Two sympatric forms appear to be in the Sierra Nevada, differing in lip morphology and scent.

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

Coastal plants of Piperia michaelii are stouter, have more stem bracts and denser inflorescences, and are later blooming than interior populations. Occasionally the seeds of plants in interior locations are brown. Where P. michaelii and P. elongata are sympatric, the former blooms earlier than the latter.

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

Source FNA vol. 26, p. 575. FNA vol. 26, p. 576.
Parent taxa Orchidaceae > subfam. Orchidoideae > tribe Orchideae > subtribe Orchidinae > Piperia Orchidaceae > subfam. Orchidoideae > tribe Orchideae > subtribe Orchidinae > Piperia
Sibling taxa
P. candida, P. colemanii, P. cooperi, P. elegans, P. elongata, P. leptopetala, P. michaelii, P. transversa, P. yadonii
P. candida, P. colemanii, P. cooperi, P. elegans, P. elongata, P. leptopetala, P. transversa, P. unalascensis, P. yadonii
Synonyms Spiranthes unalascensis, Habenaria schischmareffiana, Habenaria unalaschensis, Platanthera foetida, Platanthera unalaschcensis Habenaria michaelii, P. elongata subsp. michaelii
Name authority (Sprengel) Rydberg: Bull. Torrey Bot. Club 28: 270. (1901) (Greene) Rydberg: Bull. Torrey Bot. Club 28: 640. (1901)
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