Purchase Wildflower playing cards at select retailers in the sierra nevada or online at amazon

When plants produce multiple flowers on a single stem, it is called an inflorescence. When the individual flowers that comprise an inflorescence are small, numerous, and clustered, it is easy to mistakenly regard the inflorescence as a single flower. The Castilleja plants on the previous page have inflorescences that are sometimes incorrectly perceived as flowers. This page will highlight additional plants whose inflorescences take prominence over individual flowers.

Lupines are common in California. The state has 70 native lupine species, with numerous varieties, resulting in more than 100 recognized taxa, many of which occur in the Sierra. Lupines sometimes form large populations, dominating hillsides, meadows, or the shoulders of roadways. The visual impact of an entire population blooming simultaneously, or even the admiration for a single plant’s flower spike, can lead someone to lose focus on the individual flowers.

A lupine’s inflorescence is a raceme, an unbranched stem often containing dozens of individual flowers attached by short flower stalks of similar length, spaced equally apart and spiraling or whorled along the stem. The oldest, earliest opening flowers are located at the bottom of the raceme, and the youngest, latest opening flowers are at the top.

Each bilateral lupine flower has five petals. The top standard or banner petal covers the lower four petals on an immature flower. As the flower matures, the banner stands upright. The two side petals are the wings, and the two lower, partially fused petals form the keel.

The wings and keel often hide the pistil and stamens. Each flower has ten partially fused stamens. Five have short filaments and long anthers; five have long filaments and short anthers. A single pistil with a superior ovary and a long style bears a minute stigma.

Most lupines are cross-pollinated. Lupine plants lack nectar; they attract pollinators through scent, pollen, and brightly colored flowers. Many lupine flowers are blue or purple, but may also be white, pink, or yellow. Color variation occurs between species and sometimes within species, resulting in multicolored populations.

It is challenging to identify individual lupine species. The distinction between two species may come down to something as specific as the presence or absence of tiny hairs on the keel or the width-to-length ratio of the banner petal. This is complicated by the tendency of separate perennial species to hybridize. 

However, recognizing a plant as belonging to the genus Lupinus is straightforward. In addition to the familiar inflorescence, plants have distinctive palmately compound leaves. Each leaf comprises multiple leaflets, which attach at the end of the leaf stem (petiole) and radiate outward in different directions, like the fingers on a hand. 

Lupines also have characteristic legume fruits. At maturity, the fruit, a pea-like seed pod, dries and splits open on two seams to release multiple seeds. 

The photo of the Shaggyhair Lupine  

(Lupinus spectabilis) illustrates the characteristic inflorescence, leaf structure, and fruit of a lupine plant. Shaggyhair Lupine  is a rare species with a distribution limited to the foothills of Tuolumne and Mariposa Counties, CA.

Lupines provide numerous ecosystem services. Most notably, lupines have mutualistic associations with nitrogen-fixing bacteria housed in the plant’s root nodules. The bacteria convert atmospheric nitrogen into compounds that the lupine plants can utilize. These nitrogen compounds also leach into the soil, enriching it and fertilizing nearby plants. In addition, lupines stabilize the soil and are among the first plants to reestablish after fire.

Chick Lupine (Lupinus microcarpus densiflorus) is an annual, spring-blooming, lupine with a wide distribution, growing in barren or disturbed areas below 5,200 feet. Plants may grow to 2.5 feet. Flowers are white, pink, purple, or yellow, arranged in distinct, widely separated whorls.

As the stem of Chick Lupine ages, it bends sideways, and individual flower stalks bend upward to maintain each flower’s orientation. This results in all seed pods forming on one side of the stem.  

Gray’s Lupine (Lupinus grayi) is an attractive medium-sized lupine found in open conifer forests from 1,600 to 8,200 feet. The flowers, blooming from May to July, are deep purple to light blue, with a yellow spot on the banner petal that turns red with age. Leaves are covered with silvery hairs, giving them a gray-green appearance.

It is rarely a good idea to identify a lupine species solely by flower color. However, if you spot a lupine in the Sierra with yellow banner petals and pink wing petals, it is safe to assume it is a Harlequin Lupine (Lupinus stiversii).

The Harlequin Lupine is limited to California, yet it may be locally common below 7,200 feet in dry open locations. It grows to about 1.5 feet and blooms from April to June. The plant is sparsely hairy, with true green leaves, generally with 5-8 leaflets that broaden from the attachment point and are rounded at the tips, sometimes with a terminal point.

Members of the pea family, Fabaceae, like lupines, are ideal for observing the growth of a plant's fruit from the ovary. As shown in the photo, the superior ovary of the Harlequin Lupine flower swells to form the legume fruit as seeds develop inside. Floral structures are still attached. Eventually, the stamens and petals are shed, leaving mature fruits similar to those shown in the previous photo of the Shaggyhair Lupine.

Lupines vary in size. Silver Bush Lupine (Lupinus albifrons albifrons) is a large, showy plant, common below 5,000 feet in California's Sierra and coastal regions. The plant is a perennial with a distinct trunk, growing several feet tall with multiple inflorescences up to a foot long. The flower wing petals are purple to lavender. Banner petals start out white and change to magenta as the flowers age. Leaves have 6-10 leaflets with silvery hairs.

Unlike most lupine species, which thrive in dry, nutrient-poor soils, Large Leaf Lupine (Lupinus polyphyllus burkei) is adapted to wet locations, such as wet meadows and streambanks. Large Leaf Lupine differs from the other moisture-loving species, Broadleaf Lupine (Lupinus latifolius), by having basal leaves at the time of flowering.

Among the smallest lupine species is the Bajada Lupine (Lupinus concinnus), which grows to less than one foot tall. This primarily Southern Californian species has isolated populations located on lava caps below 5.600 feet in the Sierra.

As its name suggests, miniature or Bicolor Lupine (Lupinus bicolor) is another small species. This common plant grows in open and disturbed areas below 5,300 feet. The plant’s flowers are small and arranged in two to five, often well-spaced whorls. The front of the flower banner is white, turning pink and eventually magenta as the flower ages. The banner petal is longer than it is wide.

Sky Lupine (Lupinus nanus) often grows in large populations, forming beautiful displays on hillsides and in fields. Sky Lupine and Miniature Lupine have similar distributions, bloom times, and habitats. Sky Lupine typically has larger, more densely spaced flowers than Miniature Lupine. A particularly robust Miniature Lupine may look like Sky Lupine. One distinction is that the Sky Lupine flower has a banner petal whose width is equal to or greater than its length. 

Brewer’s Lupine (Lupinus breweri) is a mat-forming perennial, growing to less than 8 inches tall, found in open forest locations above 3,000 feet.

Lobb’s Lupine (Lupinus lepidus lobbii) is a plant of dry, rocky subalpine and alpine locations. Its leaves are distinctly hairy to shaggy, with 5-7 leaflets and long petioles. Flower stalks are erect or often spreading. 

Spider Lupine (Lupinus benthamii) is a spring bloomer growing on rocky, open slopes below 5,000 feet. A medium-sized lupine growing to just over two feet, this plant’s flowers have blue petals with a white banner spot that turns magenta on older flowers. The palmately compound leaves have seven to ten thin, linear, “spider leg-like” leaflets.

In the Sierra, the dogbane family, Apocynaceae, is represented by only a handful of native plants, including Bitter Dogbane, Indian Hemp, and several milkweed species. “Milk” in the name milkweed appropriately refers to the white latex sap that oozes out of these plants when injured. “Weed” is far less appropriate, as milkweeds are beautiful native plants that serve valuable ecosystem functions and have been historically valuable plants to Native Americans.

Numerous milkweed flowers form an inflorescence known as an umbel, in which several flower stalks of equal length extend from a single point. (Think of an umbrella frame.) Initially, flower buds are tightly packed together. As the buds develop, the flower stalks grow outward from the apex of a plant’s stem or the nodes of upper leaves. At flower maturity, the umbel becomes an attractive dome of flowers.

Individual milkweed flowers are complex with modified structures. In the mature flower, five fused petals fold back, concealing five sepals and revealing the flower’s crown or corona. The corona has five unique hood structures, which contain nectar and, in some species, have horns. In the center of the flower, stamens are fused to the pistil, forming a column. Unlike most flowers, the anthers and stigma are enclosed.

Insects searching for nectar on a milkweed flower may get a foot caught in one of the stigma slits located on the central column. As they pull their foot upward, they snag an anther gland (corpusculum) just above the slit, which is attached to two pollen sacs (pollinia) by anther arms. This releases pollen sacs from pouches located on either side of the slit. The pollen sacs may then attach to the insect and be transported by the pollinator and inserted into a stigma slit of another flower.

A milkweed plant may have many flowers. Each flower is capable of producing up to two fruits, yet a typical plant produces just a few fruits. The fruit, a seed pod known as a follicle, dries and splits open on one side, releasing large numbers of seeds with silky tufts called floss for wind dispersal.

All milkweed photos thusfar have been of Showy Milkweed (Asclepias speciosa). In California, Showy Milkweed is primarily found in the northern and central regions at elevations below 6,200 feet. The one to four-foot-tall plants have thick stems and elliptic-shaped leaves with short, soft hairs, giving the foliage a green-gray appearance. Flowers have long, pointed hoods that radiate outward, collectively resembling a five-pointed star. Horns are long and curve inward. Petals are pink. 

Milkweeds are essential to the Monarch Butterfly's survival, not only as food for the larval stage but also as protection from predators. Milkweeds are mildly toxic with bitter chemicals.  However, Monarch Butterfly larvae feed exclusively on milkweed leaves, unfazed by the plant's bitter toxicity.  As larvae digest the leaves, they store and concentrate these compounds. The bitter chemical remains in the adult butterfly, making it unpalatable to potential predators such as birds.  

Purple Milkweed or Heartleaf Milkweed (Asclepias cordifolia) is shown in the previous photo with the Monarch Butterfly. In California, this plant may be found below 6,500 feet in coastal mountains north of San Frasciso, the Sierra Nevada, and the Cascade Mountains. Purple Milkweed grows from one to three feet in height. Its foliage is mostly hairless and blue-green, with tinges of purple. The leaves are heart- or arrowhead-shaped, often with distinct veins.

Purple Milkweed’s umbel is more open and less spherical than that of Showy Milkweed. The flowers follow the same basic milkweed structure, although the horns are absent. The pinkish-white, cup-shaped hoods have a slit and small, paired, blunt tips. Petals are deep reddish-purple. Purple Milkweed blooms from May to July.

The seed pods of Purple Milkweed are similar to those of Showy Milkweed but have a smoother surface. Inside the follicle, the seeds are located at the broader base, while the attached floss is oriented vertically upward toward the narrower tip. As the seed leaves the pod, it may still be attached to the follicle by the floss. This causes the silky tuft to balloon out. Eventually, the floss detaches and functions as a parachute.

Narrow-leaf Milkweed (Asclepias fascicularis) is common in many plant communities. It grows below 7,200 feet in dry locations having moisture below the surface, such as roadside ditches and near lakes. The two to three-foot plant can be identified by its multiple stems, with whorled, green, hairless, linear leaves, one to five inches long and about 1/4 inch wide. Narrow-leaf Milkweed is common in many plant communities. 

The flowers of Narrow-leaf Milkweed are small and numerous. Petals are mauve or pale yellow-green. The sides of the cup-shaped, whiteish hoods are higher outwardly and taper toward the center of the flower. Horns are prominently curved. Narrow-leaf milkweed’s follicle is long and narrow. This plant blooms from May to October.

On the western slope of the Sierra, Indian or Kotolo Milkweed (Asclepias eriocarpa) grows in dry areas below 6,200 feet. It is found in the northern and southern regions, but is absent in the central counties. Indian Milkweed is a hairy plant growing to three feet tall, with six-inch-long oblong leaves.  Flower petals are cream, greenish, or pink. Hoods are pinkish-white. Horns are short, rising slightly above hoods (not pictured). Indian Milkweed blooms from May to October.

California Milkweed (Asclepias californica) is a central-to-southern California species. In the western Sierra foothills, it occurs in Mariposa County and regions south. This sprawling plant with lance-shaped leaves has woolly foliage, making it well adapted to hot, dry environments.

From a distance, California Milkweed may appear weedy and unattractive. Take a closer look. The pink-to-purple-red petals and deep-purple-red hoods contrast strikingly with the backdrop of California Milkweed’s silvery-white leaves. The flowers of these plants lack horns. California Milkweed blooms from April to July.

In the same family as milkweeds, but belonging to a different genus, Bitter or Spreading Dogbane (Apocynum androsaemifolium) shares many characteristics with milkweeds. These include a milky latex sap, toxicity, high nectar production, and fruits with follicles that produce wind-dispersed seeds. 

Bitter Dogbane is a three-foot-tall, branched, shrub-like plant found throughout the Sierra Nevada below 8,200 feet. Leaves are oval or egg-shaped. Bitter Dogbane has an inflorescence called a chyme, having lateral branches that all end in a single terminal flower. This plant blooms from May to October.

Both Bitter Dogbane and milkweeds are ideal plants for attracting butterflies to your garden and are available at native plant nurseries.  Native Americans used these plants for numerous medicinal purposes. The plants’ fibers may be used for making cords.