''Lasthenia burkei'' is a rare species of flowering plant in the family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...

known by the common names Burke's goldfields and Burke's baeria.

Distribution

The plant is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

, where it is known from three counties north of the

San Francisco Bay Area The San Francisco Bay Area, often referred to as simply the Bay Area, is a populous region surrounding the San Francisco, San Pablo, and Suisun Bay estuaries in Northern California. The Bay Area is defined by the Association of Bay Area Go ...

. It grows in moist spring meadows and

vernal pool Vernal pools, also called vernal ponds or ephemeral pools, are seasonal pools of water that provide habitat for distinctive plants and animals. They are considered to be a distinctive type of wetland usually devoid of fish, and thus allow the safe ...

Critically endangered plant

This is a listed endangered species on the federal level in the United States and the state level in California. It is listed as Critically Imperiled—Critically endangered by

NatureServe NatureServe, Inc. is a non-profit organization based in Arlington County, Virginia, US, that provides proprietary wildlife conservation-related data, tools, and services to private and government clients, partner organizations, and the public. Nat ...

. There are probably fewer than ten occurrences in

Lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

, Mendocino, and Sonoma Counties.''Lasthenia burkei''.

The Nature Conservancy The Nature Conservancy (TNC) is a global environmental organization headquartered in Arlington, Virginia. it works via affiliates or branches in 79 countries and territories, as well as across every state in the US. Founded in 1951, The Nat ...

It is threatened by the destruction and degradation of its rare

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The p ...

habitat, and it may be extinct by 2025.

Description

''Lasthenia burkei'' is an erect annual herb producing hairy stems with sparse linear or deeply divided, narrow, pointed leaves a few centimeters long. Atop the stem is an

inflorescence An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

, which is a

flower head A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, compos ...

with a base of hairy

phyllaries In botanical terminology, a phyllary, also known an involucral bract or tegule, is a single bract of the involucre of a composite flower. The involucre is the grouping of bracts together. Phyllaries are reduced leaf-like structures that form one o ...

. The head contains many yellow disc florets surrounded by a fringe of several short ray florets, which are usually also yellow. The fruit is a hairy, club-shaped achene less than 2 millimeters long.

References

External links

Jepson Manual Treatment: ''Lasthenia burkei''USDA Plants ProfileCenter for Plant Conservation Profile''Lasthenia burkei'' — U.C. Photo gallery
{{Taxonbar, from=Q12061103 burkei Endemic flora of California Natural history of Lake County, California Natural history of Mendocino County, California Natural history of Sonoma County, California Critically endangered flora of California