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Physaria alpestris

alpine twin-pod, Washington bladder-pod, Washington twin-pod

Chambers' bladder-pod, Chambers' physaria, Chambers' twinpod, double bladderpod

Habit Perennials; caudex usually simple, rarely branched, (cespitose); (silvery) pubescent throughout, trichomes several-rayed, rays (1- or) 2-bifurcate, (low-umbonate, tubercles relatively few, small). Perennials; caudex usually simple, sometimes branched, (thick, cespitose); (silvery) pubescent throughout, trichomes few-rayed, rays furcate, sometimes slightly fused at base, (umbonate, lightly tuberculate to nearly smooth).
Stems

several from base, decumbent to ascending, (unbranched), 0.5–1.5 dm.

several from base, erect or decumbent (arising laterally, unbranched), 0.5–1.5 mm.

Basal leaves

(petiole slender);

blade obovate, 3–5 cm (width 10–20 mm, base tapering abruptly to petiole), margins entire, (apex rarely slightly acute).

(petiole slender);

blade obovate to orbicular, 3–6 cm (width 10–20 mm), margins entire or dentate.

Cauline leaves

blade oblanceolate, 0.5–1.5 cm (width 3–5 mm), margins entire.

blade spatulate, 1–2 cm (width 3–6 mm), margins entire, (apex often acute).

Racemes

subcorymbose.

congested.

Flowers

sepals oblong, 8–10 mm;

petals spatulate, 12–14 mm.

sepals narrowly lanceolate, 5–8(–9) mm;

petals narrowly oblanceolate, 9–12 mm, (claw undifferentiated from blade).

Fruiting pedicels

(divaricate, straight), 5–10 mm.

(divaricate, slightly sigmoid), 8–15 mm.

Fruits

didymous, mostly highly inflated (strongly flattened at least in 1/2 toward replum), 14–18 × 14–18 mm, (papery, basal sinus slightly notched, apical open, shallow);

valves (retaining seeds after dehiscence), evenly pubescent;

replum lanceolate, 7–10 mm, width 1.5–2.5 mm, as wide as or wider than fruit, apex acute to acuminate;

ovules 8–10 per ovary;

style 5–7 mm.

(often purplish in age), didymous, subreniform, strongly inflated, 9–18 × 11–21(–30) mm, (papery, base obtuse to slightly cordate, apical sinus V-shaped or convex, open crests rounded);

valves (2-keeled on side away from replum, each 3-sided, keels rounded, sides flat or slightly convex, retaining seeds after dehiscence), evenly and densely pubescent;

replum oblong, as wide as or wider than fruits, apex obtuse;

ovules 4–12 per ovary;

style (4–)6–8 mm (exceeding sinus).

Seeds

flattened, (2–3 mm).

flattened.

2n

= 48–52, 52, 64, 67–70.

= 8, 10, 16, 24.

Physaria alpestris

Physaria chambersii

Phenology Flowering May–Jun. Flowering Apr–Jul.
Habitat Alpine scree, rocky ridges, talus slopes, volcanic sands and gravel, serpentine gravel, granitic slopes, mountain shrub, subalpine fir, and whitebark pine communities Clay hillsides, limestone gravel, dolomite ridges, roadbanks, loose gravel, reddish clay, sagebrush and pinyon-juniper areas
Elevation (700-)1300-2400 m ((2300-)4300-7900 ft) 1500-3200 m (4900-10500 ft)
Distribution
from FNA
WA
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; ID; NV; OR; UT
[WildflowerSearch map]
[BONAP county map]
Discussion

Physaria chambersii has been divided into three varieties based on whether the fruit is stipitate (var. canaani) or not, and whether the caudex elongates (var. sobolifera) or not (var. chambersii). In this species and in some others, e.g., P. newberryi, the latter character often depends on substrate and microclimate. Shifting substrates, such as moving sand and talus, often cause caudices to elongate. The species can be confused with 57. P. newberryi.

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

Source FNA vol. 7, p. 624. FNA vol. 7, p. 631.
Parent taxa Brassicaceae > tribe Physarieae > Physaria Brassicaceae > tribe Physarieae > Physaria
Sibling taxa
P. acutifolia, P. alpina, P. angustifolia, P. arctica, P. arenosa, P. argyraea, P. arizonica, P. aurea, P. bellii, P. brassicoides, P. calcicola, P. calderi, P. carinata, P. chambersii, P. cinerea, P. condensata, P. congesta, P. cordiformis, P. curvipes, P. densiflora, P. didymocarpa, P. dornii, P. douglasii, P. eburniflora, P. engelmannii, P. eriocarpa, P. fendleri, P. filiformis, P. floribunda, P. fremontii, P. garrettii, P. geyeri, P. globosa, P. gooddingii, P. gordonii, P. gracilis, P. grahamii, P. hemiphysaria, P. hitchcockii, P. humilis, P. integrifolia, P. intermedia, P. kingii, P. klausii, P. lata, P. lepidota, P. lesicii, P. lindheimeri, P. ludoviciana, P. macrocarpa, P. mcvaughiana, P. montana, P. multiceps, P. navajoensis, P. nelsonii, P. newberryi, P. obcordata, P. obdeltata, P. occidentalis, P. oregona, P. ovalifolia, P. pachyphylla, P. pallida, P. parviflora, P. parvula, P. pendula, P. pinetorum, P. prostrata, P. pruinosa, P. pulvinata, P. purpurea, P. pycnantha, P. rectipes, P. recurvata, P. reediana, P. rollinsii, P. saximontana, P. scrotiformis, P. sessilis, P. spatulata, P. subumbellata, P. tenella, P. thamnophila, P. tumulosa, P. valida, P. vicina, P. vitulifera
P. acutifolia, P. alpestris, P. alpina, P. angustifolia, P. arctica, P. arenosa, P. argyraea, P. arizonica, P. aurea, P. bellii, P. brassicoides, P. calcicola, P. calderi, P. carinata, P. cinerea, P. condensata, P. congesta, P. cordiformis, P. curvipes, P. densiflora, P. didymocarpa, P. dornii, P. douglasii, P. eburniflora, P. engelmannii, P. eriocarpa, P. fendleri, P. filiformis, P. floribunda, P. fremontii, P. garrettii, P. geyeri, P. globosa, P. gooddingii, P. gordonii, P. gracilis, P. grahamii, P. hemiphysaria, P. hitchcockii, P. humilis, P. integrifolia, P. intermedia, P. kingii, P. klausii, P. lata, P. lepidota, P. lesicii, P. lindheimeri, P. ludoviciana, P. macrocarpa, P. mcvaughiana, P. montana, P. multiceps, P. navajoensis, P. nelsonii, P. newberryi, P. obcordata, P. obdeltata, P. occidentalis, P. oregona, P. ovalifolia, P. pachyphylla, P. pallida, P. parviflora, P. parvula, P. pendula, P. pinetorum, P. prostrata, P. pruinosa, P. pulvinata, P. purpurea, P. pycnantha, P. rectipes, P. recurvata, P. reediana, P. rollinsii, P. saximontana, P. scrotiformis, P. sessilis, P. spatulata, P. subumbellata, P. tenella, P. thamnophila, P. tumulosa, P. valida, P. vicina, P. vitulifera
Synonyms Lesquerella alpestris P. chambersii var. canaani, P. chambersii var. sobolifera
Name authority Suksdorf: W. Amer. Sci. 15: 58. (1906) Rollins: Rhodora 41: 403, plate 556, figs. 15–18. (1939)
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