Dudleya blochmaniae subsp. brevifolia
Encyclopedia
Dudleya blochmaniae subsp. brevifolia is a succulent plant known by the common name Short-leaved Liveforever or Short-leaved Dudleya. This plant is a rare subspecies
of Dudleya blochmaniae
with an extremely limited and endemic range in San Diego County, California
.
with cone-shaped leaves along its hidden stem. It may be brown, reddish-purple, or greenish and bears a branching inflorescence
with a few flowers per branch, each opening into a star-shaped bloom with five pointed petals. It sprouts after significant winter rains (December to February) and flowers from May to June. It produces a many-seeded fruit from a simple pistil, which disperses seeds along a single suture. It is only found on bare surface hardpans of Torrey
sandstone with minimal topsoil. Small marble-sized, iron-bearing granules are present at all sites and are likely an edaphic requirement.
Total population estimates vary by year and by researcher. Extensive studies have been completed on Carmel Mountain, Carmel Valley
, San Diego. The Multiple Species Conservation Program (MSCP) of San Diego County estimated the Carmel Mountain population at just 1446 individuals in 2002, and at 113,134 individuals in 2006. Most recently, in 2008, UCLA faculty Dr. Hartmut S. Walter and Matthew Luskin estimated the Carmel Mountain population at over 100,000 individuals. Their population is highly dependent on rainfall, exploding in population when there is annual rainfall over 10 inches, and drastically shrinking when there is less than 4 inches of annual rainfall.
, Carmel Mountain (on multiple sites), Crest Canyon, Skeletal Canyon, and Torrey Pines Extension. The total habitat outside of the Torrey Pines State Reserve
that contains this species was estimated at just 2,667 square meters.
Dudleya blochmaniae subsp. brevifolia is listed as an endangered species
in California
(listed January 1982). On October 7, 1996, the U.S. Fish and Wildlife Service withdrew federal protection as an endangered species citing the threats to the species had diminished and that it was a "covered species" within the Multiple Species Conservation Program
(MSCP) of southern San Diego County.
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of Dudleya blochmaniae
Dudleya blochmaniae
Dudleya blochmaniae is a succulent plant known by the common name Blochman's liveforever or Blochman's dudleya. This plant is native to California and Baja California, where it grows along the coastline.-Description:...
with an extremely limited and endemic range in San Diego County, California
San Diego County, California
San Diego County is a large county located in the southwestern corner of the US state of California. Hence, San Diego County is also located in the southwestern corner of the 48 contiguous United States. Its county seat and largest city is San Diego. Its population was about 2,813,835 in the 2000...
.
Description
It grows into a somewhat erect, small (1–4 cm), cryptic, and corm-like succulent perennialPerennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...
with cone-shaped leaves along its hidden stem. It may be brown, reddish-purple, or greenish and bears a branching 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...
with a few flowers per branch, each opening into a star-shaped bloom with five pointed petals. It sprouts after significant winter rains (December to February) and flowers from May to June. It produces a many-seeded fruit from a simple pistil, which disperses seeds along a single suture. It is only found on bare surface hardpans of Torrey
Torrey
-Places:* Torrey Pines High School* Torrey Pines Golf Course* Torrey Pines State Reserve* Torrey Pines Gliderport-Torrey :* Charles Cutler Torrey , American ancient historian and archaeologist...
sandstone with minimal topsoil. Small marble-sized, iron-bearing granules are present at all sites and are likely an edaphic requirement.
Total population estimates vary by year and by researcher. Extensive studies have been completed on Carmel Mountain, Carmel Valley
Carmel Valley
The Carmel Valley AVA is an American Viticultural Area in Monterey County, California, east of Carmel-by-the-Sea. The AVA is home to a number of wineries and vineyards, as well as the town of Carmel Valley Village...
, San Diego. The Multiple Species Conservation Program (MSCP) of San Diego County estimated the Carmel Mountain population at just 1446 individuals in 2002, and at 113,134 individuals in 2006. Most recently, in 2008, UCLA faculty Dr. Hartmut S. Walter and Matthew Luskin estimated the Carmel Mountain population at over 100,000 individuals. Their population is highly dependent on rainfall, exploding in population when there is annual rainfall over 10 inches, and drastically shrinking when there is less than 4 inches of annual rainfall.
Conservation
Dudleya blochmaniae subsp. brevifolia is a high conservation priority because it exists only in these 5 locations (listed by decreasing average yearly population): Torrey Pines State ReserveTorrey Pines State Reserve
Torrey Pines State Natural Reserve is a coastal state park located in the California community of La Jolla, San Diego, California, off North Torrey Pines Road . Although it is located within San Diego city limits, it remains one of the wildest stretches of land on the Southern California coast...
, Carmel Mountain (on multiple sites), Crest Canyon, Skeletal Canyon, and Torrey Pines Extension. The total habitat outside of the Torrey Pines State Reserve
Torrey Pines State Reserve
Torrey Pines State Natural Reserve is a coastal state park located in the California community of La Jolla, San Diego, California, off North Torrey Pines Road . Although it is located within San Diego city limits, it remains one of the wildest stretches of land on the Southern California coast...
that contains this species was estimated at just 2,667 square meters.
Dudleya blochmaniae subsp. brevifolia is listed as an 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...
in 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...
(listed January 1982). On October 7, 1996, the U.S. Fish and Wildlife Service withdrew federal protection as an endangered species citing the threats to the species had diminished and that it was a "covered species" within the Multiple Species Conservation Program
Multiple Species Conservation Program
The Multiple Species Conservation Program will preserve a network of habitat and open space, protecting bio-diversity and enhancing the region's quality of life.The City of San Diego is one of several jurisdictions participating in the MSCP...
(MSCP) of southern San Diego County.