Lasthenia burkei
Encyclopedia
Lasthenia burkei is a rare species of flowering plant in the daisy family
known by the common names Burke's goldfields and Burke's baeria. It is endemic to California
, where it is known from three counties north of the San Francisco Bay Area
. It grows in moist spring meadows and vernal pool
s. This 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
, which is a flower head
with a base of hairy phyllaries
. 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.
This is a listed endangered species
on the federal level in the United States and the California state level. There are probably fewer than ten occurrences in Lake
, Mendocino
, and Sonoma Counties
. It is threatened by the destruction and degradation of its rare wetland
habitat, and it may be extinct
by 2025.
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...
known by the common names Burke's goldfields and Burke's baeria. It is endemic to California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, where it is known from three counties north of the San Francisco Bay Area
San Francisco Bay Area
The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...
. It grows in moist spring meadows and vernal pool
Vernal pool
Vernal pools, also called vernal ponds or ephemeral pools, are temporary pools of water. They are usually devoid of fish, and thus allow the safe development of natal amphibian and insect species...
s. This 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
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
, which is a flower head
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....
with a base of hairy phyllaries
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...
. 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
Achene
An achene is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent...
less than 2 millimeters long.
This is a listed endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
on the federal level in the United States and the California state level. There are probably fewer than ten occurrences in Lake
Lake County, California
Lake County is a county located in the north central portion of the U.S. state of California, north of the San Francisco Bay Area. It takes its name from Clear Lake, the dominant geographic feature in the county and the largest natural lake wholly within California...
, Mendocino
Mendocino County, California
Mendocino County is a county located on the north coast of the U.S. state of California, north of the greater San Francisco Bay Area and west of the Central Valley. As of the 2010 census, the population was 87,841, up from 86,265 at the 2000 census...
, and Sonoma Counties
Sonoma County, California
Sonoma County, located on the northern coast of the U.S. state of California, is the largest and northernmost of the nine San Francisco Bay Area counties. Its population at the 2010 census was 483,878. Its largest city and county seat is Santa Rosa....
. It is threatened by the destruction and degradation of its rare wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
habitat, and it may be extinct
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
by 2025.