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Cypripedium californicum

California lady slipper, California lady's-slipper

Cypripedium montanum

mountain lady slipper, mountain lady's-slipper, white lady's-slipper

Habit Plants erect, 25–120 cm. Plants erect, 25–71 cm.
Leaves

5–10, along length of stem, alternate, ascending to spreading;

blade elliptic-lanceolate to broadly elliptic, 5–16 × 1.5–6.5 cm.

4–6, inserted toward base or scattered along stem, alternate, erect, ascending, or spreading;

blade suborbiculate or broadly ovate to elliptic-lanceolate, 3.3–17 × 2.5–9.5 cm.

Flowers

3–18(–22);

sepals yellow-green to pale brownish yellow;

dorsal sepal elliptic, 14–20 × 7–13 mm;

lateral sepals connate almost to apex;

synsepal 12–20 × 10–12 mm;

petals spreading, same color as sepals or more yellowish, linear-oblong to linear-lanceolate, flat, 14–16 × 3–5 mm;

lip white, sometimes pinkish, obovoid, 15–20 mm;

orifice basal, 11–14 mm;

staminode suborbicular-subauriform.

1–3;

sepals greenish, suffused, often heavily, with reddish brown or madder, or rarely clear green;

dorsal sepal lance-acuminate to elliptic-lance-acuminate, 33–60 × 8–16 mm;

lateral sepals connate;

synsepal 30–60 × 6–18 mm;

petals spreading-deflexed, same color as sepals, spirally twisted, linear to linear-lanceolate, 36–77 × 3–5 mm;

lip white, rarely suffused with magenta, obovoid or oblance-ovoid to oblance-fusiform, 19–33 mm;

orifice basal, 13–22 mm;

staminode lanceoloid to broadly ovoid or ellipsoid-ovoid.

Cypripedium californicum

Cypripedium montanum

Phenology Flowering May–Jun. Flowering Feb–Sep.
Habitat Forest openings, especially on steep slopes, in seeps, springy marshes Mesic to dry (rarely wet) coniferous, deciduous, and broadleaf evergreen forests, openings, and thickets, around shrubs on open slopes
Elevation 0–1600 m (0–5200 ft) 0–2400 m (0–7900 ft)
Distribution
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; CA; ID; MT; OR; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Plants of Cypripedium montanum grown in exposed, relatively sunny situations have the ascending leaves inserted along the basal portion of the stem and the flowers displayed well above the leaves. In shadier, especially sheltered sites, the spreading leaves may be more evenly scattered along the stem. In this species the apical margin of the orifice of the lip is usually acute, in common with C. candidum, and in contrast to the usually obtuse margin in C. parviflorum; this difference can aid determination of discolored herbarium specimens. Hybrids of C. montanum and C. parviflorum have been designated C. ×columbianum Sheviak. See 11. C. parviflorum for a general discussion of hybridization and variation within and between related species.

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

Source FNA vol. 26, p. 503. FNA vol. 26, p. 504.
Parent taxa Orchidaceae > subfam. Cypripedioideae > Cypripedium Orchidaceae > subfam. Cypripedioideae > Cypripedium
Sibling taxa
C. acaule, C. arietinum, C. candidum, C. fasciculatum, C. guttatum, C. kentuckiense, C. montanum, C. parviflorum, C. passerinum, C. reginae, C. yatabeanum
C. acaule, C. arietinum, C. californicum, C. candidum, C. fasciculatum, C. guttatum, C. kentuckiense, C. parviflorum, C. passerinum, C. reginae, C. yatabeanum
Name authority A. Gray: Proc. Amer. Acad. Arts 7: 389. (1868) Douglas ex Lindley: Gen. Sp. Orchid. Pl., 528. (1840)
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