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pink oxalis, pink sorrell, windowbox wood-sorrel

hairy western wood-sorrel, hairy wood sorrel

Habit Herbs perennial, acaulous, rhizomes present, thick, woody, irregularly nodulate-segmented, often covered with persistent petiole bases, stolons absent, bulbs absent. Herbs perennial, caulescent, rhizomes and stolons absent, bulbs absent.
Aerial stems

usually 2–8 from base, decumbent to ascending, 10–40 cm, becoming woody proximally, sparsely to densely pilose, hairs spreading irregularly to ± deflexed, nonseptate, longer hairs 0.6–1.2 mm.

Leaves

basal;

petiole 11–30 cm;

leaflets 3, green to purplish abaxially, green adaxially, rounded-obcordate, 18–20 mm, margins densely loosely ciliate, lobed 1/5–1/3 length, lobes apically convex, surfaces evenly strigose-villous to strigose-hirsute, oxalate deposits in dots concentrated mostly toward margins or over whole surface.

basal and cauline;

stipules oblong, margins narrowly flanged, apical auricles absent;

petiole (1–)2–6 cm, hairs nonseptate;

leaflets 3, glaucous and gray-green to yellowish green, obcordate, 5–12 mm, lobed 1/5–1/3 length, surfaces glabrous to loosely strigose to hirsute-villous, oxalate deposits absent.

Inflorescences

usually umbelliform cymes, less commonly in irregular cymes, 3–12-flowered;

scapes 12–28 cm, sparsely strigose.

umbelliform cymes, 1–2(–3)-flowered;

peduncles 1.5–5 cm.

Flowers

heterostylous;

sepal apices with 2 orange tubercles;

petals usually purplish rose to red, rarely white, 10–14 mm.

semihomostylous or distylous, within level of leaves;

sepal apices without tubercles, surfaces strigose to hirsute-strigose;

petals yellow, rarely with red lines proximally, 8–12 mm.

Capsules

ovoid, 4–8 mm, sparsely strigose.

angular-cylindric, abruptly tapering to apex, 12–17(–20) mm, strigose-hirsute.

Seeds

brown to blackish brown, transverse ridges rarely with whitish lines or spots.

2n

= 42.

Oxalis articulata

Oxalis pilosa

Phenology Flowering Mar–Jul. Flowering (Feb–)Mar–Jun(–Oct).
Habitat Disturbed places, especially near gardens, lawns, fields, roadsides. Juniper-grasslands, pinyon-juniper, oak-juniper, oak, oak-pine, rocky and grassy hillsides, riparian woods (sycamore-walnut, cottonwood-willow), canyons, stream banks, washes, gravel bars.
Elevation 0–250 m. (0–800 ft.) (700–)900–1900(–2000) m. ((2300–)3000–6200(–6600) ft.)
Distribution
from FNA
AL; AR; CA; FL; GA; LA; MS; NC; OK; OR; SC; TX; VA; South America (Argentina, Brazil, Uruguay) [Introduced in North America; introduced also in Europe, Pacific Islands (New Zealand), Australia]
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; NM; NV; OR; UT; Mexico (Baja California, Chihuahua, Coahuila, Durango, Nuevo León, Sonora)
[BONAP county map]
Discussion

Oxalis articulata in the United States commonly has been identified as O. rubra. Oxalis rubra was treated at subspecific rank by A. Lourteig (1982), but subsp. articulata and subsp. rubra have essentially the same native range and occur in similar habitats. Lourteig identified both subspecies in the United States, noting in her key that vestiture is reduced and the sepals are broader in subsp. rubra. Evidence is weak for recognizing more than a single entity. In the Flora of Panama (Lourteig 1980), she recognized only O. articulata, noting that it is naturalized in other parts of America and in the Old World.

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

Oxalis pilosa has been treated as an infraspecific entity within O. albicans, but the two are sympatric in the southwestern United States and although each is variable, there appear to be relatively few unequivocal intermediates. Reports of O. pilosa from Texas apparently were based on misidentifications of O. albicans and perhaps also of O. dillenii.

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

Source FNA vol. 12, p. 153. FNA vol. 12, p. 143.
Parent taxa Oxalidaceae > Oxalis Oxalidaceae > Oxalis
Sibling taxa
O. albicans, O. bowiei, O. brasiliensis, O. caerulea, O. californica, O. colorea, O. corniculata, O. debilis, O. decaphylla, O. dichondrifolia, O. dillenii, O. drummondii, O. florida, O. frutescens, O. grandis, O. hirta, O. hispidula, O. illinoensis, O. incarnata, O. intermedia, O. latifolia, O. laxa, O. macrantha, O. metcalfei, O. montana, O. oregana, O. pes-caprae, O. pilosa, O. purpurea, O. stricta, O. suksdorfii, O. texana, O. triangularis, O. trilliifolia, O. violacea
O. albicans, O. articulata, O. bowiei, O. brasiliensis, O. caerulea, O. californica, O. colorea, O. corniculata, O. debilis, O. decaphylla, O. dichondrifolia, O. dillenii, O. drummondii, O. florida, O. frutescens, O. grandis, O. hirta, O. hispidula, O. illinoensis, O. incarnata, O. intermedia, O. latifolia, O. laxa, O. macrantha, O. metcalfei, O. montana, O. oregana, O. pes-caprae, O. purpurea, O. stricta, O. suksdorfii, O. texana, O. triangularis, O. trilliifolia, O. violacea
Synonyms O. articulata subsp. rubra, O. rubra O. albicans subsp. pilosa, O. corniculata subsp. pilosa, O. corniculata var. pilosa, O. wrightii var. pilosa, Xanthoxalis pilosa
Name authority Savigny: in J. Lamarck et al., Encycl. 4: 686. (1798) Nuttall: in J. Torrey and A. Gray, Fl. N. Amer. 1: 212. (1838)
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