Silver Lupine (Lupinus albifrons)

Lupinus albifrons
Conservation status
Secure  (NatureServe)[1][2]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Fabales
Family:	Fabaceae
Subfamily:	Faboideae
Genus:	Lupinus
Species:	L. albifrons
Binomial name
Lupinus albifrons Benth.

Lupinus albifrons, silver lupine, white-leaf bush lupine, or evergreen lupine, is a species of lupine (lupin). It is native to California and Oregon, where it grows along the coast and in dry and open meadows, prairies and forest clearings. It is a member of several plant communities, including coastal sage scrub, chaparral, northern coastal scrub, foothill woodland, and yellow pine forest. Silver lupine is an important species for several animals throughout these ranges.

Lupinus albifrons is a perennial shrub, taking up about 2 ft (0.61 m) of space and reaching 5 ft (1.5 m). It has a light blue to violet flower on 3–12 inches (7.6–30.5 cm) stalks. The leaves are silver with a feathery texture.^[3] It grows in sandy to rocky places below 5,000 feet (1,500 m).^[4]

This plant grows as a wildflower in the hills and valleys of California. It requires good drainage and needs little water once the roots are established. When grown with tall fescue, a common grass used in California/Western Coast lawns, L. albifrons was shown to have decreased above-ground growth due to competition with the grass for soil space. Conversely, it was shown that the presence of the lupine could aid the growth of the tall fescue.^[5]

Fresh seed of L. albifrons var. flumineus is said to need no stratification in order to germinate, while stored seed germination is aided by physical scarification or a hot-water treatment typical of many other leguminous plants.^[6]

The plant is deer-resistant due to the presence of the bitter-tasting alkaloid toxins anagyrine and lupinine.^[7] Because of these toxins lupines can negatively affect livestock, causing birth defects and decreasing weight especially in young, inexperienced cattle.^[7] When cows are under stress from lactating, especially in times of low forage availability, they will consume more lupine than usual.^[7]

The federally endangered mission blue butterfly requires either Lupinus albifrons, Lupinus formosus and Lupinus variicolor, on which their larvae feed.^[8] The butterfly becomes toxic itself when it feeds on the plant, leaving it with a bitter taste to deter predators.

Due to its potential danger to livestock, this lupine is removed from rangeland when possible, eliminating a crucial food plant from the butterfly's range^{[citation needed]}.

Lupinus albifrons serves as an important nesting site for the San Miguel Island Song Sparrow (Melospiza melodia micronyx).^[9]

Pollination of Lupinus albifrons is primarily done through various species in the genus Bombus. To deter pollinators from visiting flowers that have already been pollinated, the plant produces ethylene to change the spot on its banner petals from white/pale yellow to pink and then magenta as anthocyanins accumulate.^[10]

The Painted Lady butterfly (Vanessa cardui) was shown to have a higher survival rate to the virus Junonia coenia densovirus when using L. albifrons as a host compared to Plantago lanceolata.^[11]

Lupinus albifrons has six different varieties, four of which occur only in California, the other two occur in both California and Oregon:^[12]

• Lupinus albifrons var. albifrons, silver lupine
• Lupinus albifrons var. collinus, silver lupine
• Lupinus albifrons var. douglasii, Douglas' silver lupine
• Lupinus albifrons var. eminens, silver lupine
• Lupinus albifrons var. flumineus, silver lupine.
  • Found primarily in the chaparral of Mendocino, Trinity, and Siskiyou counties.^[6]
• Lupinus albifrons var. hallii, syn. Lupinus paynei, Payne's bush lupine. ^[13]

A lupine seedling at the site of a 2004 California wildfire

Blooming silver lupine

• California chaparral and woodlands
• California coastal sage and chaparral ecoregion

• Jepson Manual Treatment - Lupinus albifrons
• CalFlora - Lupinus albifrons
• Lady Bird Johnson Wildflower Center
• Golden Gate National Recreation Area
• Lupinus albifrons - Photo gallery

Wikimedia Commons has media related to Lupinus albifrons.