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Pursh's milk-vetch, Pursh's sheeppod, woolly-pod milk-vetch

John Day milk-vetch, transparent milk-vetch

Habit Plants tuft-forming, acaulescent, subacaulescent, or shortly caulescent, 4.5–13 cm, usually villous to villous-tomentose, sometimes appearing white or gray, hairs basifixed; from branched, superficial caudex, branches with thatch. Plants annual or biennial, slender, 5–15 cm, strigulose; from superficial root-crown; taproot slender.
Stems

usually obscured by stipules, or internodes to 2 cm, villous to villous-tomentose.

usually 3–10, decumbent to ascending, strigulose.

Leaves

1–12(–15) cm;

stipules (2.5–)3–15 mm, membranous;

leaflets (3 or)5–17(–21), blades obovate, obovate-cuneate, elliptic to oblanceolate, or rhombic-elliptic, 2–14(–20) mm, apex usually acute, subacute, acuminate, or obtuse, rarely truncate-emarginate, surfaces densely villous.

2–5(–6) cm;

stipules distinct, 1.5–4 mm, papery at proximal nodes, herbaceous or submembranous at distal nodes;

leaflets (5 or)7–13, blades oblong-obovate, -ovate, or obovate-cuneate, (2–)3–12 mm, apex obtuse, truncate, or retuse, surfaces glabrous.

Racemes

1–11-flowered, flowers ascending;

axis 0.3–2(–4) cm in fruit;

bracts 2–9 mm;

bracteoles 0.

(3–)7–15-flowered, flowers ascending becoming spreading, later declined;

axis (0.4–)1–3.5(–4.5) cm in fruit;

bracts 0.8–1.8 mm;

bracteoles 0.

Peduncles

ascending or erect, decumbent in fruit, 1.5–10.5 cm.

divaricate, 1–4(–5.5) cm.

Pedicels

1–5 mm.

0.6–1.8 mm (in fruit).

Flowers

19–25(–27) mm;

calyx cylindric, cylindro-campanulate, or campanulate, (5.5–)6–16(–19) mm, villous-pilose, tube (4–)4.5–12(–13.6) mm, lobes subulate, 1–6(–7) mm;

corolla white, cream, purple, or pink-purple;

banner recurved through 40°;

keel 8–21.2(–22.5) mm.

6.7–9.1 mm;

calyx campanulate, 3.5–4.5 mm, strigulose, tube 2–2.6 mm, lobes lanceolate-subulate, 1.3–1.9 mm;

corolla whitish, banner with lavender veins;

banner incurved through 45°;

keel 4.1–5.7 mm, apex obtuse, sometimes obscurely beaklike.

Legumes

initially ascending (humistrate), brownish, not mottled or spotted, incurved, ovoid, ovoid-ellipsoid, or lanceoloid-ellipsoid, dorsiventrally compressed, 7–26(–30) × 3.5–11(–13) mm, unilocular, fleshy becoming leathery, mostly shaggy-villous, sometimes tomentose or villous-hirsute, hairs 1.6–4(–5) mm, often concealing surface;

sessile or subsessile, or gynophore 0.5+ mm.

deflexed or declined, purplish green becoming stramineous then brownish, lunately incurved, usually obliquely linear-oblong, oblanceoloid, or semi-ellipsoid, rarely semi-ovoid, somewhat inflated, almost bladdery, usually ± 3-sided compressed, (10–)15–28 × 3–9 mm, unilocular or subunilocular, thin becoming papery-membranous, translucent, sparsely and minutely strigulose, hairs straight, appressed;

seed-bearing flange to 2.5 mm wide, septum 0.5–1 mm.

Seeds

14–38(–46).

(6–)8–14.

2n

= 28.

Astragalus purshii

Astragalus diaphanus

Phenology Flowering Apr–Jun.
Habitat Gravelly soils overlying basalt, sandbars, sandy banks.
Elevation 50–600 m. (200–2000 ft.)
Distribution
from USDA
w North America
[WildflowerSearch map]
[BONAP county map]
from FNA
OR
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 8 (8 in the flora).

The geographic distribution of Astragalus purshii, forming a relatively large triangle in western North America, from southwestern Canada to southern California, northeastward to western North Dakota, makes it the most widely distributed of all astragali with woolly fruits. The case for specific status for such entities as A. inflexus and A. utahensis may be little stronger than that for several of the taxa included within A. purshii (D. Isely 1998). L. Abrams (1944b) often gave an inclusive name of woolly-pod to all of the fuzzy-podded species, sometimes sheep-pod. For consistency they are all called milkvetch here. Isely gave a synopsis that helped to distinguish other woolly fruited species. The treatment of R. C. Barneby (1964) is followed here, and his key to varieties is largely followed.

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

Astragalus diaphanus occurs along the John Day River from near Dayville in Grant County, Oregon, westward along the Columbia River to slightly south of The Dalles, but is considered extirpated in Washington. R. C. Barneby (1964) discussed variation in this species in detail and compared it with A. wetherillii, a species disjunct by hundreds of kilometers in west-central Colorado.

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

Key
1. Calyces (5.5–)6–10.1 mm; banners 9–16.5 mm; keel 8–13 mm.
→ 2
2. Racemes (3–)5–11-flowered; leaflets (7 or)9–15(or 17); sw Idaho.
var. ophiogenes
2. Racemes 1–5(–7)-flowered; leaflets (3 or)5–9(or 11); California, sw Idaho, nw Nevada, and along foothills and plains adjacent to e slope of Cascades in Oregon.
→ 3
3. Legumes incurved only in beak; seeds 24–32; San Bernardino Mountains and Sierra Nevada, California, w Nevada.
var. lectulus
3. Legumes arched throughout, at least through 0.5–1 spiral; seeds 14–20; plains of ne California to c Oregon, sw Idaho, and nw Nevada.
var. lagopinus
1. Calyces (8–)9–16(–19) mm; banners (14.6–)15.4–25(–26) mm; keel (11.5–)12.4–21.2(–22.5) mm.
→ 4
4. Corollas mostly white or cream (keel tip maculate), rarely banners and wings tipped dull, pale bluish purple; widespread from California and British Columbia eastward to North Dakota and Colorado.
var. purshii
4. Corollas purple or pink-purple throughout; British Columbia to s California (cis- and transmontane), sw Montana, and sc Nevada.
→ 5
5. Banners (14.6–)19–25(–26.5) mm; keel (11.5–)12.4–21(–22.5) mm.
→ 6
6. Plants acaulescent or subacaulescent; leaflets (5 or)7 or 9(or 11), blades obovate, obovate-cuneate, or broadly elliptic, apices obtuse or truncate; ec Idaho, sw Montana.
var. concinnus
6. Plants shortly caulescent or subacau­lescent; leaflets (3 or)5–17(–21), blades obovate-cuneate, oblanceolate, nar­rowly elliptic or elliptic-oblanceolate, apices usually acute, subacute, or short-acuminate, rarely obtuse; British Columbia, California, Idaho, Nevada, Oregon, Utah, Washington.
→ 7
7. Legumes not or very shallowly sulcate ventrally; leaflets (3 or)5–13(–17), blades usually obovate-cuneate or oblanceolate, rarely elliptic-oblanceolate, apices usually acute or subacute, rarely obtuse; racemes 3–11-flowered; banners (14.6–)15.4–25 mm; cis- and trans­montane California, w Nevada, and Oregon.
var. tinctus
7. Legumes strongly depressed-sulcate ventrally in proximal 1/2; leaflets (7 or)9–15(or 17), blades usually narrowly elliptic, rarely elliptic-oblanceolate, apices usually acute or short-acuminate; racemes 2–5(–10)-flowered; banners 19–25(–26.5) mm; Oregon and British Columbia eastward to Utah.
var. glareosus
5. Banners 11.5–18(–25) mm; keel 10.2–15(–20.8) mm.
→ 8
8. Legumes strongly sulcate ventrally in proximal 1/2; c Nevada.
var. pumilio
8. Legumes not or shallowly sulcate ventrally; ne California, sw Idaho, nw Nevada, se Oregon.
→ 9
9. Legumes 13–23(–27) mm; racemes with relatively short (subcapitate) flowering axes; ne California, nw Nevada, e Oregon.
var. tinctus
9. Legumes 8–13 mm; racemes with relatively long flowering axes; along Owyhee, Snake, and lower Bruneau rivers, se Oregon and sw Idaho.
var. ophiogenes
Source FNA vol. 11. FNA vol. 11.
Parent taxa Fabaceae > subfam. Faboideae > Astragalus > sect. Argophylli Fabaceae > subfam. Faboideae > Astragalus > sect. Inflati
Sibling taxa
A. accidens, A. accumbens, A. ackermanii, A. acutirostris, A. adanus, A. aequalis, A. agnicidus, A. agrestis, A. albens, A. albulus, A. allochrous, A. alpinus, A. altus, A. alvordensis, A. amblytropis, A. americanus, A. amnis-amissi, A. amphioxys, A. ampullarioides, A. ampullarius, A. andersonii, A. anisus, A. anserinus, A. applegatei, A. aquilonius, A. aretioides, A. argophyllus, A. aridus, A. arizonicus, A. arrectus, A. arthurii, A. asclepiadoides, A. asotinensis, A. asymmetricus, A. atratus, A. atropubescens, A. atwoodii, A. austiniae, A. australis, A. barnebyi, A. barrii, A. beathii, A. beatleyae, A. beckwithii, A. bernardinus, A. bibullatus, A. bicristatus, A. bisulcatus, A. bodinii, A. bolanderi, A. bourgovii, A. brandegeei, A. brauntonii, A. brazoensis, A. breweri, A. californicus, A. callithrix, A. calycosus, A. camptopus, A. canadensis, A. caricinus, A. casei, A. castaneiformis, A. castetteri, A. ceramicus, A. cerussatus, A. chamaeleuce, A. chamaemeniscus, A. chinensis, A. chloödes, A. chuskanus, A. cibarius, A. cicer, A. cimae, A. claranus, A. clevelandii, A. cliffordii, A. cobrensis, A. coccineus, A. collinus, A. coltonii, A. columbianus, A. concordius, A. congdonii, A. conjunctus, A. consobrinus, A. contortuplicatus, A. convallarius, A. cottamii, A. crassicarpus, A. cremnophylax, A. cronquistii, A. crotalariae, A. curtipes, A. curvicarpus, A. cusickii, A. cutleri, A. cyaneus, A. cymboides, A. deanei, A. debequaeus, A. desereticus, A. desperatus, A. deterior, A. detritalis, A. diaphanus, A. didymocarpus, A. distortus, A. diversifolius, A. douglasii, A. drabelliformis, A. drummondii, A. duchesnensis, A. eastwoodiae, A. egglestonii, A. emoryanus, A. endopterus, A. ensiformis, A. episcopus, A. equisolensis, A. eremiticus, A. ertterae, A. eucosmus, A. eurekensis, A. eurylobus, A. falcatus, A. feensis, A. filipes, A. flavus, A. flexuosus, A. fucatus, A. funereus, A. gambelianus, A. geyeri, A. gibbsii, A. giganteus, A. gilensis, A. gilmanii, A. gilviflorus, A. glycyphyllos, A. gracilis, A. grayi, A. gypsodes, A. hallii, A. hamiltonii, A. harrisonii, A. heilii, A. henrimontanensis, A. holmgreniorum, A. hoodianus, A. hornii, A. howellii, A. humillimus, A. humistratus, A. hyalinus, A. hypoxylus, A. inflexus, A. insularis, A. inversus, A. inyoensis, A. iodanthus, A. iodopetalus, A. iselyi, A. jaegerianus, A. jejunus, A. johannis-howellii, A. kelseyae, A. kentrophyta, A. kerrii, A. knightii, A. laccoliticus, A. lancearius, A. laxmannii, A. layneae, A. leibergii, A. lemmonii, A. lentiformis, A. lentiginosus, A. leptaleus, A. leptocarpus, A. leucolobus, A. limnocharis, A. lindheimeri, A. linifolius, A. loanus, A. lonchocarpus, A. lotiflorus, A. lutosus, A. lyallii, A. macrodon, A. magdalenae, A. malacoides, A. malacus, A. megacarpus, A. michauxii, A. microcymbus, A. microcystis, A. microlobium, A. micromerius, A. miguelensis, A. minthorniae, A. misellus, A. miser, A. missouriensis, A. moencoppensis, A. mohavensis, A. mollissimus, A. molybdenus, A. monoensis, A. montii, A. monumentalis, A. mulfordiae, A. multiflorus, A. musiniensis, A. naturitensis, A. neglectus, A. nelsonianus, A. neomexicanus, A. nevinii, A. newberryi, A. nidularius, A. nothoxys, A. nudisiliquus, A. nutans, A. nutriosensis, A. nuttallianus, A. nuttallii, A. nutzotinensis, A. nyensis, A. obcordatus, A. obscurus, A. oniciformis, A. oocalycis, A. oocarpus, A. oophorus, A. oreganus, A. osterhoutii, A. oxyphysus, A. pachypus, A. palmeri, A. panamintensis, A. pardalinus, A. parryi, A. pattersonii, A. pauperculus, A. paysonii, A. peckii, A. pectinatus, A. perianus, A. phoenix, A. pictiformis, A. pinonis, A. piscator, A. piutensis, A. plattensis, A. platytropis, A. polaris, A. pomonensis, A. porrectus, A. praelongus, A. preussii, A. proimanthus, A. proximus, A. pseudiodanthus, A. pterocarpus, A. pubentissimus, A. pulsiferae, A. puniceus, A. pycnostachyus, A. racemosus, A. rafaelensis, A. rattanii, A. ravenii, A. recurvus, A. reflexus, A. remotus, A. reventiformis, A. reventus, A. riparius, A. ripleyi, A. robbinsii, A. rusbyi, A. sabulonum, A. sabulosus, A. salmonis, A. saurinus, A. scaphoides, A. schmolliae, A. sclerocarpus, A. scopulorum, A. sepultipes, A. serenoi, A. sericoleucus, A. serpens, A. sesquiflorus, A. sheldonii, A. shevockii, A. shortianus, A. siliceus, A. simplicifolius, A. sinuatus, A. solitarius, A. sophoroides, A. soxmaniorum, A. spaldingii, A. sparsiflorus, A. spatulatus, A. speirocarpus, A. straturensis, A. striatiflorus, A. subcinereus, A. subvestitus, A. succumbens, A. tegetarioides, A. tener, A. tennesseensis, A. tephrodes, A. terminalis, A. tetrapterus, A. thurberi, A. tibetanus, A. tidestromii, A. tiehmii, A. titanophilus, A. toanus, A. toquimanus, A. tortipes, A. traskiae, A. tricarinatus, A. trichopodus, A. tridactylicus, A. troglodytus, A. tweedyi, A. tyghensis, A. umbellatus, A. umbraticus, A. uncialis, A. utahensis, A. vaccarum, A. vallaris, A. vexilliflexus, A. villosus, A. wardii, A. waterfallii, A. webberi, A. welshii, A. wetherillii, A. whitneyi, A. williamsii, A. wingatanus, A. wittmannii, A. woodruffii, A. wootonii, A. wrightii, A. xiphoides, A. yoderwilliamsii, A. zionis
A. accidens, A. accumbens, A. ackermanii, A. acutirostris, A. adanus, A. aequalis, A. agnicidus, A. agrestis, A. albens, A. albulus, A. allochrous, A. alpinus, A. altus, A. alvordensis, A. amblytropis, A. americanus, A. amnis-amissi, A. amphioxys, A. ampullarioides, A. ampullarius, A. andersonii, A. anisus, A. anserinus, A. applegatei, A. aquilonius, A. aretioides, A. argophyllus, A. aridus, A. arizonicus, A. arrectus, A. arthurii, A. asclepiadoides, A. asotinensis, A. asymmetricus, A. atratus, A. atropubescens, A. atwoodii, A. austiniae, A. australis, A. barnebyi, A. barrii, A. beathii, A. beatleyae, A. beckwithii, A. bernardinus, A. bibullatus, A. bicristatus, A. bisulcatus, A. bodinii, A. bolanderi, A. bourgovii, A. brandegeei, A. brauntonii, A. brazoensis, A. breweri, A. californicus, A. callithrix, A. calycosus, A. camptopus, A. canadensis, A. caricinus, A. casei, A. castaneiformis, A. castetteri, A. ceramicus, A. cerussatus, A. chamaeleuce, A. chamaemeniscus, A. chinensis, A. chloödes, A. chuskanus, A. cibarius, A. cicer, A. cimae, A. claranus, A. clevelandii, A. cliffordii, A. cobrensis, A. coccineus, A. collinus, A. coltonii, A. columbianus, A. concordius, A. congdonii, A. conjunctus, A. consobrinus, A. contortuplicatus, A. convallarius, A. cottamii, A. crassicarpus, A. cremnophylax, A. cronquistii, A. crotalariae, A. curtipes, A. curvicarpus, A. cusickii, A. cutleri, A. cyaneus, A. cymboides, A. deanei, A. debequaeus, A. desereticus, A. desperatus, A. deterior, A. detritalis, A. didymocarpus, A. distortus, A. diversifolius, A. douglasii, A. drabelliformis, A. drummondii, A. duchesnensis, A. eastwoodiae, A. egglestonii, A. emoryanus, A. endopterus, A. ensiformis, A. episcopus, A. equisolensis, A. eremiticus, A. ertterae, A. eucosmus, A. eurekensis, A. eurylobus, A. falcatus, A. feensis, A. filipes, A. flavus, A. flexuosus, A. fucatus, A. funereus, A. gambelianus, A. geyeri, A. gibbsii, A. giganteus, A. gilensis, A. gilmanii, A. gilviflorus, A. glycyphyllos, A. gracilis, A. grayi, A. gypsodes, A. hallii, A. hamiltonii, A. harrisonii, A. heilii, A. henrimontanensis, A. holmgreniorum, A. hoodianus, A. hornii, A. howellii, A. humillimus, A. humistratus, A. hyalinus, A. hypoxylus, A. inflexus, A. insularis, A. inversus, A. inyoensis, A. iodanthus, A. iodopetalus, A. iselyi, A. jaegerianus, A. jejunus, A. johannis-howellii, A. kelseyae, A. kentrophyta, A. kerrii, A. knightii, A. laccoliticus, A. lancearius, A. laxmannii, A. layneae, A. leibergii, A. lemmonii, A. lentiformis, A. lentiginosus, A. leptaleus, A. leptocarpus, A. leucolobus, A. limnocharis, A. lindheimeri, A. linifolius, A. loanus, A. lonchocarpus, A. lotiflorus, A. lutosus, A. lyallii, A. macrodon, A. magdalenae, A. malacoides, A. malacus, A. megacarpus, A. michauxii, A. microcymbus, A. microcystis, A. microlobium, A. micromerius, A. miguelensis, A. minthorniae, A. misellus, A. miser, A. missouriensis, A. moencoppensis, A. mohavensis, A. mollissimus, A. molybdenus, A. monoensis, A. montii, A. monumentalis, A. mulfordiae, A. multiflorus, A. musiniensis, A. naturitensis, A. neglectus, A. nelsonianus, A. neomexicanus, A. nevinii, A. newberryi, A. nidularius, A. nothoxys, A. nudisiliquus, A. nutans, A. nutriosensis, A. nuttallianus, A. nuttallii, A. nutzotinensis, A. nyensis, A. obcordatus, A. obscurus, A. oniciformis, A. oocalycis, A. oocarpus, A. oophorus, A. oreganus, A. osterhoutii, A. oxyphysus, A. pachypus, A. palmeri, A. panamintensis, A. pardalinus, A. parryi, A. pattersonii, A. pauperculus, A. paysonii, A. peckii, A. pectinatus, A. perianus, A. phoenix, A. pictiformis, A. pinonis, A. piscator, A. piutensis, A. plattensis, A. platytropis, A. polaris, A. pomonensis, A. porrectus, A. praelongus, A. preussii, A. proimanthus, A. proximus, A. pseudiodanthus, A. pterocarpus, A. pubentissimus, A. pulsiferae, A. puniceus, A. purshii, A. pycnostachyus, A. racemosus, A. rafaelensis, A. rattanii, A. ravenii, A. recurvus, A. reflexus, A. remotus, A. reventiformis, A. reventus, A. riparius, A. ripleyi, A. robbinsii, A. rusbyi, A. sabulonum, A. sabulosus, A. salmonis, A. saurinus, A. scaphoides, A. schmolliae, A. sclerocarpus, A. scopulorum, A. sepultipes, A. serenoi, A. sericoleucus, A. serpens, A. sesquiflorus, A. sheldonii, A. shevockii, A. shortianus, A. siliceus, A. simplicifolius, A. sinuatus, A. solitarius, A. sophoroides, A. soxmaniorum, A. spaldingii, A. sparsiflorus, A. spatulatus, A. speirocarpus, A. straturensis, A. striatiflorus, A. subcinereus, A. subvestitus, A. succumbens, A. tegetarioides, A. tener, A. tennesseensis, A. tephrodes, A. terminalis, A. tetrapterus, A. thurberi, A. tibetanus, A. tidestromii, A. tiehmii, A. titanophilus, A. toanus, A. toquimanus, A. tortipes, A. traskiae, A. tricarinatus, A. trichopodus, A. tridactylicus, A. troglodytus, A. tweedyi, A. tyghensis, A. umbellatus, A. umbraticus, A. uncialis, A. utahensis, A. vaccarum, A. vallaris, A. vexilliflexus, A. villosus, A. wardii, A. waterfallii, A. webberi, A. welshii, A. wetherillii, A. whitneyi, A. williamsii, A. wingatanus, A. wittmannii, A. woodruffii, A. wootonii, A. wrightii, A. xiphoides, A. yoderwilliamsii, A. zionis
Subordinate taxa
A. purshii var. concinnus, A. purshii var. glareosus, A. purshii var. lagopinus, A. purshii var. lectulus, A. purshii var. ophiogenes, A. purshii var. pumilio, A. purshii var. purshii, A. purshii var. tinctus
Synonyms A. diurnus, A. drepanolobus
Name authority Douglas in W. J. Hooker: Fl. Bor.-Amer. 1: 152. (1831) Douglas in W. J. Hooker: Fl. Bor.-Amer. 1: 151. (1831)
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