Astragalus lemmonii
Encyclopedia
Astragalus lemmonii, the Lemmon’s milkvetch, is a rare plant
of eastern California
. It is a member of the bean
family, the Leguminosae (a.k.a. Fabaceae
), and specifically a member of the subfamily Papilionoideae (a.k.a. Faboideae
). The genus Astragalus
is a large genus within this family; members of this genus are known as milkvetches or locoweeds. Close relatives of this particular species include Astragalus peckii and Astragalus lentiformis
.
, loosely matted to open and widely branched, herbage green but sparsely strigose, with basifixed hairs.
Its several stems are slender and radiates from a superficial root-crown, prostrate to procumbent, herbaceous
to the base, 10–50 cm, very sparsely strigose, floriferous from near the base. The stipules submembranous, semi- or fully amplexicaul but free, 2–5 mm.
The leaves measures 1–4½ cm. Leaflets are 7–15, narrowly elliptic, lanceolate to oblong to oblanceolate; tips acute, subacute, or exceptionally emarginate; sparingly appressed-pubescent, 2–11 mm. The terminal leaflet is generally much broader than the subfiliform rachis
.
s are several and are often paired in the axils. These are distal, often 2 or 3 in one axil, one raceme
of each pair usually developing much sooner than the other.
The peduncle
s are slender, filiform, incurved-ascending at anthesis
, mostly 1–2 cm long (much shorter than the leaves). Several (2-13) flowers are clustered at the ends of the peduncles. These flowers are ascending in subcapitate racemes. The flower's calyx are thinly white- or partly black-strigulose to silky-villous; calyx-tube short-campanulate, ca. 2 mm, 4 mm high; the alternate setaceous-subulate calyx teeth equaling or longer than the tube, ca. 1½ mm. The corolla is ochroleucous (whitish), tinged or veined with dull lilac or purple; banner 4¾–6 mm, moderately recurved (45–85°); wings nearly as long; very obtuse keel, 3½–4 mm.
The pods are small, sessile
, puberulent to strigose, spreading to declined, often humistrate, in profile ovoid-oblong, straight or a trifle incurved, obtuse at base, abruptly acute at apex to short-mucronate, thickened, incompletely to fully bilocular (2-celled), cordate in cross-section, trigonous or compressed-triquetrous, the lateral faces flat, the dorsal (upper or adaxial) face narrower and sulcate (grooved), carinate by the ventral suture, the dorsal suture shallowly to deeply sulcate; thin, papery, green to stramineous (brownish) valves strigulose, 4–7 mm long, 1½ -2½ mm in diameter, deciduous
from receptacle, dehiscence primarily basal and occurs after falling. The ovary
is strigulose and contains a few seeds (ovules 4–8).
Found in moist places within Great Basin sagebrush scrub communities. More specifically, in moist grassy, sedgy, or rushy flats bordering streams and lake shores; vernally moist summer-dry alkaline meadows, seeps, marsh
es and swamp
s; occasionally found in non-wetland
s. Found in rare and scattered colonies. Elevation of occurrence is 4,200 to 7,225 feet above mean sea level. Fire does not propagate well in the habitat of A. lemmonii, although the fire tolerance of the species itself is not known.
, Revisio Generum Plantarum
2: 946. 1891.
Rare species
A rare species is a group of organisms that are very uncommon or scarce. This designation may be applied to either a plant or animal taxon, and may be distinct from the term "endangered" or "threatened species" but not "extinct"....
of eastern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. It is a member of the bean
Bean
Bean is a common name for large plant seeds of several genera of the family Fabaceae used for human food or animal feed....
family, the Leguminosae (a.k.a. Fabaceae
Fabaceae
The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...
), and specifically a member of the subfamily Papilionoideae (a.k.a. Faboideae
Faboideae
Faboideae is a subfamily of the flowering plant family Fabaceae or Leguminosae. One acceptable alternative name for the subfamily is Papilionoideae....
). The genus Astragalus
Astragalus
Astragalus is a large genus of about 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae, subfamily Faboideae. The genus is native to temperate regions of the Northern Hemisphere...
is a large genus within this family; members of this genus are known as milkvetches or locoweeds. Close relatives of this particular species include Astragalus peckii and Astragalus lentiformis
Astragalus lentiformis
Astragalus lentiformis is a species of milkvetch known by the common name lens-pod milkvetch. It is endemic to the Sierra Nevada in eastern Plumas County, California, where it grows in scrub and coniferous forest.-Description:...
.
Description
The plant is a perennial plant. It has a fleshy to woody taprootTaproot
A taproot is an enlarged, somewhat straight to tapering plant root that grows vertically downward. It forms a center from which other roots sprout laterally.Plants with taproots are difficult to transplant...
, loosely matted to open and widely branched, herbage green but sparsely strigose, with basifixed hairs.
Its several stems are slender and radiates from a superficial root-crown, prostrate to procumbent, herbaceous
Herbaceous plant
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...
to the base, 10–50 cm, very sparsely strigose, floriferous from near the base. The stipules submembranous, semi- or fully amplexicaul but free, 2–5 mm.
The leaves measures 1–4½ cm. Leaflets are 7–15, narrowly elliptic, lanceolate to oblong to oblanceolate; tips acute, subacute, or exceptionally emarginate; sparingly appressed-pubescent, 2–11 mm. The terminal leaflet is generally much broader than the subfiliform rachis
Rachis
Rachis is a biological term for a main axis or "shaft".-In zoology:In vertebrates a rachis can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the rachis usually form the supporting axis of the body and is then called the spine or vertebral column...
.
Inflorescence
The inflorescenceInflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
s are several and are often paired in the axils. These are distal, often 2 or 3 in one axil, one raceme
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...
of each pair usually developing much sooner than the other.
The peduncle
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...
s are slender, filiform, incurved-ascending at anthesis
Anthesis
Anthesis is the period during which a flower is fully open and functional. It may also refer to the onset of that period.The onset of anthesis is spectacular in some species. In Banksia species, for example, anthesis involves the extension of the style far beyond the upper perianth parts...
, mostly 1–2 cm long (much shorter than the leaves). Several (2-13) flowers are clustered at the ends of the peduncles. These flowers are ascending in subcapitate racemes. The flower's calyx are thinly white- or partly black-strigulose to silky-villous; calyx-tube short-campanulate, ca. 2 mm, 4 mm high; the alternate setaceous-subulate calyx teeth equaling or longer than the tube, ca. 1½ mm. The corolla is ochroleucous (whitish), tinged or veined with dull lilac or purple; banner 4¾–6 mm, moderately recurved (45–85°); wings nearly as long; very obtuse keel, 3½–4 mm.
The pods are small, sessile
Sessility (botany)
In botany, sessility is a characteristic of plants whose flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel...
, puberulent to strigose, spreading to declined, often humistrate, in profile ovoid-oblong, straight or a trifle incurved, obtuse at base, abruptly acute at apex to short-mucronate, thickened, incompletely to fully bilocular (2-celled), cordate in cross-section, trigonous or compressed-triquetrous, the lateral faces flat, the dorsal (upper or adaxial) face narrower and sulcate (grooved), carinate by the ventral suture, the dorsal suture shallowly to deeply sulcate; thin, papery, green to stramineous (brownish) valves strigulose, 4–7 mm long, 1½ -2½ mm in diameter, deciduous
Deciduous
Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...
from receptacle, dehiscence primarily basal and occurs after falling. The ovary
Ovary
The ovary is an ovum-producing reproductive organ, often found in pairs as part of the vertebrate female reproductive system. Ovaries in anatomically female individuals are analogous to testes in anatomically male individuals, in that they are both gonads and endocrine glands.-Human anatomy:Ovaries...
is strigulose and contains a few seeds (ovules 4–8).
Distribution, habitat, and ecology
The plant is described as "scattered and not common." It ranges from eastern foothills of the Cascades in south-western Oregon to the Sierra Nevada of southern Inyo county in California, extending a little into Washoe county in far-western Nevada.Found in moist places within Great Basin sagebrush scrub communities. More specifically, in moist grassy, sedgy, or rushy flats bordering streams and lake shores; vernally moist summer-dry alkaline meadows, seeps, marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
es and swamp
Swamp
A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or swamp...
s; occasionally found in non-wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
s. Found in rare and scattered colonies. Elevation of occurrence is 4,200 to 7,225 feet above mean sea level. Fire does not propagate well in the habitat of A. lemmonii, although the fire tolerance of the species itself is not known.
Conservation status and threats
- U.S. Forest ServiceUnited States Forest ServiceThe United States Forest Service is an agency of the United States Department of Agriculture that administers the nation's 155 national forests and 20 national grasslands, which encompass...
Pacific Southwest Region Sensitive Species. - California Native Plant SocietyCalifornia Native Plant SocietyThe California Native Plant Society is a California not-for-profit organization that seeks to increase understanding of California's native flora and to preserve that flora. Its "paramount purpose is to preserve wild plants".-History:...
List 1B.2. List 1B: Rare, threatened, or endangered in California and elsewhere; 0.2: Fairly endangered in California - NatureServeNatureServeNatureServe is a non-profit conservation organization whose mission is to provide the scientific basis for effective conservation action. NatureServe and its network of natural heritage programs are the leading source for information about rare and endangered species and threatened ecosystems in...
California State Rank S2.2; Global Rank G3. - Some of the principal threats to this species are land conversion and pipeline construction.
Field identification
The characteristic blooming period for this species is late May to early August, which time window is also considered the best period for definitive identification.Synonymy
Tragacantha lemmonii (A. Gray) KuntzeOtto Kuntze
Otto Carl Ernst Kuntze was a German botanist.-Biography:Otto Kuntze was born in Leipzig.An apothecary in his early career, he published an essay entitled Pocket Fauna of Leipzig. Between 1863 and...
, Revisio Generum Plantarum
Revisio Generum Plantarum
Revisio Generum Plantarum, also known by its standard botanical abbreviation Revis. Gen. Pl., is a botanic treatise by Otto Kuntze...
2: 946. 1891.