[Lupines East of the Cascade Mountains of Oregon and Washington]

Silvery Lupine

Lupinus argenteus var. argenteus

Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii 

Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii)

Silvery lupine as seen along US Highway 20 near Riley, Oregon..............May 30, 2012.

Characteristics:

Silvery lupine is a widespread lupine, and exhibits many variations in its characteristics, which has resulted in its division into about a dozen varieties. Because of this variation, I presume that at least some of the varieties may be classified with different species at some point in the future (one example is Lupinus argenteus var. heteranthus, which may have been reclassified to L. caudatus, the Kellogg's spurred lupine.).

Silvery lupine is an upright perennial with one to several green or purplish stems from 1.5-7 dm in height. Typically, one can identify this species from a distance as it often lacks basal leaves during flowering. If they are present when in bloom, the petioles will be less than three times the length of their leaflets. The compound-palmate leaves are usually found on the stems. The petioles of the leaves range from 2-8 cm long, with the 6-10 leaflets ranging from 2-7 cm long and 3-18 mm wide. The individual leaflets are linear-oblanceolate/elliptic to broadly oblanceolate in shape.

The racemes are typically solitary and terminal, arising above the highest leaves. Occasionally, smaller secondary racemes may arise from lateral branches. The flowers are scattered with the petals usually blue, sometimes lavender, pink, puple, or white. The banner, which is 4-14 mm long, has a yellowish-white eye. The banner is sparsely, if at all, haired on its back. The upper calyx lobe would usually cover any such hairs.The wing petals are from 5-14 mm long with the keel about as long as the wings. The calyx is variable, often spurred, but also frequently lacking a spur.The calyx is 4.5-10 mm in lengthm typically covered with appressed hairs. In south-central Oregon, bloomtime may range from mid-May to well into September and October.


Habitat:

Silvery lupine may be found in open ponderosa pine forests, throughout the sagebrush plains, and into the juniper forest of the intermountain west.


Range:

Silvery lupine may be found widely across the Great Basin and northeastward into the Rocky Mountains of Montana and Wyoming.


Close-up sideview of a flower of Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii - Close-up of a raceme of Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii) - Close-up image of the keel of a flower of Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii)

Close-ups of the flowers of silvery lupine as seen along US Highway 20 near Riley, Oregon..........May 30, 2012.

Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii) - Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii) - Inflorescence of Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii) - Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii)

Silvery lupine as seen along the Rimrock Springs Trail #850 in the Crooked River National Grasslands.........May 20, 2017.

Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii) - Silvery lupine: Lupinus argenteus var. argenteus (Synonyms: Lupinus argenteus ssp. argenteus, Lupinus corymbosus, Lupinus johannis-howellii)

Silvery lupine in bloom along the Rimrock Springs Trail #850 in the Crooked River National Grasslands.........June 24, 2017.

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Silvery lupine near Silver Lake, OR..........June 26, 1995. Note the lack of basal leaves. During wetter summers, these plants continue to bloom into early September around this location.

Paul Slichter