Common Goldenstar

Bloomeria crocea

Light and dark yellow flowers blooming
Stonebridge Mesa | May 2019

Common goldenstars (Bloomeria crocea) are spring perennials with sparse, grass-like foliage and long, leafless stems that bear terminal bursts of starry flowers.

Goldenstars grow from corms, which like bulbs allow the plant to survive extended periods of unfavorable environments.  During most years, common goldenstars are uncommon in the Reserve, but after a wet winter, a sparkling display may develop on Stonebridge Mesa, turning the green, grassy fields golden.

Other Common Names:

Common Goldenstars

Description 4,21,23,59,290,306,490

Common goldenstar is a perennial that grows from a fibrous-coated underground corm (a modified stem, sometimes mistaken for a bulb). There is a single grass-like leaf or occasionally two.23 The bright green leaf is linear, flat or V-shaped in cross section and six to 20 or more inches long (15-500 cm). Leaves are difficult to distinguish from the surrounding vegetation and often die back before the flower stalk appears.

Flowers occur in airy umbels of a few to 50 or more flowers, ½ – 1 ¼ inches (1.2 – 3.2 cm) across, on top of a long, leafless stalk.  The individual flowers radiate on long pedicels from a single point – like a star burst. Some say the flowers “twinkle” in the late afternoon sun, giving the plant its common name. 23,174 Sepals and petals are indistinguishable, together called tepals.  The six tepals are yellow, with a brownish, or sometimes greenish, mid-vein stripe that gives the bud an attractive, amber pattern. There is a single pistil with a three-chambered, superior ovary on a short stalk. The ovary is obovoid, with three major lobes, each with two shallow lobes. The single style has a small, three-lobed stigma. There are six stamens, three somewhat longer than the others. Anthers are pale yellow to lilac. The bases of the filaments are modified into flattened, wing- or cup-shaped nectar-producing appendages, which have tiny lateral cusps. These appendages form a nectar cup around the base of the ovary and are a distinguishing taxonomic feature. The major period of bloom is between April and June.468

The fruit is an ellipsoid capsule, on which the style remains as a small beak. The fruit develops within the envelope of the dried tepals. When mature, the capsule splits, releasing small dark, irregular, rough-textured seeds.

Common Goldenstar young spring leaves

Young Spring leaves | Santa Carina trailhead | April 2019

Yellow flower with six petals

Photo credit: Barbara Wallach | April 2016

Developing seeds. Common Goldenstar

Developing seeds | Stonebridge Mesa | June 2019

Distribution 7,11,59,89,468

Common goldenstars are native to southern California and northern Baja California, west of the Coast and Peninsular Ranges, below 5600 feet. They prefer openings in woodland, chaparral and sage scrub vegetations, especially dry slopes. They are often common after fire or other disturbance.

The best place to view goldenstars in the Reserve is on the  grassy slopes of Stonebridge Mesa. They also occur occasionally in a small opening along the main trail in East Basin, but this patch is slowly being overgrown by surrounding vegetation.


Goldenstars are perennial monocots in the brodiaea family (Themidaceae).   This family is a small family of western North America with ten,some say eleven, genera.2 In past taxonomic arrangements, species now in the brodiaea family have been placed within the lily family (Liliaceae306), the onion family (Alliaceae34), the amarylis family (Amaryllidaceae23) and the asparagus family (Asparagaceae).341 There is still disagreement among experts.493

Within the small brodiaea family, Bloomeria is a genus of only three species, all native to central and southern California and northern Baja California. There are three varieties of B. crocea, distinguished by the size and shape of the tiny cusps on the filament appendages. Our variety is var. crocea.

Jepson eFlora Taxon Page
Yellow flowers growing in dry brown patch

Stonebridge Mesa | May 2011

Yellow flowers in green field

Stonebridge Mesa | March 2019

Flower showing nectar cup around base of ovary;Common Goldenstar

Flower showing nectar cup around base of ovary | Stonebridge Mesa | May 2019


Goldenstars are geophytes.341 This is a diverse group of plants with subsurface food storage structures that allow them to survive periods of unfavorable conditions, such as drought or fire. Many geophytes are monocots, including all those with bulbs (such as lilies, tulips and daffodils), corms (such as crocus and daffodils) and rhizomes (such as iris and cattails.

The degree of protection depends upon the depth of the bulb or corm in the ground. Many plants, including geophytes have specialized roots, called contractile roots that serve to pull the corm (or other storage structure) downward.487,488,492 Contractile roots are shorter and thicker than the roots for water uptake. When active, a contractile root widens at the upper end, shortening the root while the lower end anchors the plant. The combined forces gradually pull the corm downward. In addition, the expansion of the upper root loosens the soil, easing the movement of the corm. The resultant pulling power of one contractile root is high, equivalent to the pulling power of a small mammal’s muscle, but the pulling action is slow – 22 days vs a few milliseconds – and the action of one root occurs only one time. The combined force of many contractile roots can move a plant a significant distance. One experiment487 showed a bulb moving 4 inches (10 cm) deeper during the course of 20 weeks.

Field full of yellow flowers

Stonebridge Mesa | May 2019

Opened yellow flowers and dying brown flowers

Stonebridge Mesa | May 2017

Yellow flower with six petals

Santa Carina trailhead | May 2015

Human Uses

Like most wild bulbs and corms, goldenstar corms were eaten by several southern California tribes17,34,75,282. In addition, the Kawaiisu of Central California mashed the corms by rubbing them on metates. The resultant paste was used seal the spaces of their seed-gathering baskets.34,282

Group of yellow flowers in green field

Stonebridge Mesa | May 2019

Yellow flowers opening

Stonebridge Mesa | May 2011

Yellow flowers

Photo credit: Barbara Wallach | April 2016

Interesting Facts 491

Common goldenstars grow from corms; lilies, such as tulips grow from bulbs and iris grow from rhizomes. Do you know the difference?

All are modified stems and all serve as storage organs, but their structures and modes of operation differ.  A corm is a swollen, underground stem base. There is a growing point on the top, and on the bottom, there is a basal plate from which the roots grow. The surface of a corm may be covered with remains of last year’s leaves, or scales, but the energy-rich tissue is the solid interior. A corm lasts only a single year. At the end of its life cycle, it produces new corms (cormels). Other familiar species that grow from corms include crocuses and gladiolas

A bulb is short underground stem which encloses an embryonic plant and is completely surrounded by fleshy, modified leaves that store food for future growth. Unlike a corm, which has a solid interior, the interior of a bulb is layered – like an onion. A bulb may live one or many years. New bulbs (bulblets) are formed from lateral buds around the base. Many flowers grow from bulbs, including tulips, daffodils, lilies and onions. Native bulb plants in the Reserve include star lilies and mariposa lilies.

A rhizome is a thickened stem that grows partially, or entirely underground, often horizontally. Roots grow along the lower surface and there is generally a growing point at the tip and others along the rhizome’s length. Each growing point can become a new plant. Common rhizomatous plants in the Reserve are blue-eyed grass and southern cattail.


Field of yellow flowers

Stonebridge Mesa | May 2019

Yellow flowers and green unopened buds

Stonebridge Mesa | April 2019

mature seed capsule of Common Goldenstar

Fruit and mature seed | Stonebridge Mesa | June 2019

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