''Dipterostemon'' is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s in the family

Asparagaceae Asparagaceae (), known as the asparagus family, is a family of flowering plants, placed in the order Asparagales of the monocots. The family name is based on the edible garden asparagus, '' Asparagus officinalis''. This family includes both ...

. Its only species is ''Dipterostemon capitatus'',

synonym A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

''Dichelostemma capitatum'', known by the common names blue dicks, wild hyacinth, purplehead and brodiaea (alternately spelled brodiea and brodeia), native to the Western United States (particularly

Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

Utah Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northea ...

, and

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

) and northwest

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

Description

''Dipterostemon capitatus'' is an herbaceous

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

growing from an underground

corm Corm, bulbo-tuber, or bulbotuber is a short, vertical, swollen, underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat (perennation). The word ''c ...

to a height of as much as 60 cm. It has 2–3 leaves which are 10–40 cm long. The inflorescence is

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...

- or

umbel UMBEL (Upper Mapping and Binding Exchange Layer) is a logically organized knowledge graph of 34,000 concepts and entity types that can be used in information science for relating information from disparate sources to one another. It was retired ...

-like, and dense. It usually contains 2 to 15 flowers, which have a blue, blue-purple, pink-purple, or white

perianth The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower. It is a structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepal ...

. The flower tube is 3–12 mm and is narrowly cylindrical to campanulate. Flowers have six fertile

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s, deeply notched, lanceolate, white, angled inward, slightly reflexed at tip, with outer filaments wider at the base. It has a twisted and fleshy peduncle, a set of membranous, petal-like stamen appendages around the anthers, and angular black

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

s. It reproduces from seed and vegetative means in the form of cormlets. The cormlets are attached to the parent corm by

stolon In biology, a stolon ( from Latin ''wikt:stolo, stolō'', genitive ''stolōnis'' – "branch"), also known as a runner, is a horizontal connection between parts of an organism. It may be part of the organism, or of its skeleton. Typically, animal ...

s and are sessile, produced in the axils of the old leaf bases on the mature corm. Plants thrive in open disturbed environments, and are a common post-fire

succession Succession is the act or process of following in order or sequence. Governance and politics *Order of succession, in politics, the ascension to power by one ruler, official, or monarch after the death, resignation, or removal from office of ...

species in

chaparral Chaparral ( ) is a shrubland plant plant community, community found primarily in California, southern Oregon, and northern Baja California. It is shaped by a Mediterranean climate (mild wet winters and hot dry summers) and infrequent, high-intens ...

. Flowering peaks in March.Dichelostemma capitatum
at iNaturalist ''D. capitatus'' occurs from sea level up to 2,300 meters. It inhabits a wide variety of plant communities, including

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 saf ...

s, valley

grassland A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceo ...

, scrub,

coniferous forest Conifers () are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All e ...

s, and open

woodland A woodland () is, in the broad sense, land covered with woody plants (trees and shrubs), or in a narrow sense, synonymous with wood (or in the U.S., the '' plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunli ...

s. It seems not to colonize after fire by seed, but rather by cormlets. After fire, plants are exposed to unshaded environments with little brush competition, and vigorously flower in open environments with increased soil nutrients. Grasslands that have been burned may exhibit thousands of plants where none have appeared in recent years. Corms may sit for a decade or more and wait for fire or other favorable environmental conditions before breaking ground. Suppression of fire may cause increased shade and plant competition and decrease population numbers of ''D. capitatus''.

Taxonomy

The species was first described by

George Bentham George Bentham (22 September 1800 – 10 September 1884) was an English botanist, described by the weed botanist Duane Isely as "the premier systematic botanist of the nineteenth century". Born into a distinguished family, he initially studie ...

in 1857 as ''Brodiaea capitata''. In 1868, Alphonso Wood moved it to the genus ''

Dichelostemma ''Dichelostemma'' is a genus of North American plants closely related to the genus ''Brodiaea'' and sometimes regarded as part of that group. ''Dichelostemma'' is classified in the Brodiaeoideae, cluster-lily subfamily within the Asparagaceae, ...

'' as ''Dichelostemma capitatum''. In 1912,

Per Axel Rydberg Per Axel Rydberg (July 6, 1860 – July 25, 1931) was a Swedish-born, American botanist who was the first curator of the New York Botanical Garden Herbarium. Biography Per Axel Rydberg was born in Odh, Västergötland, Sweden and emigrated to ...

moved it to ''Dipterostemon'' as ''Dipterostemon capitatus''. Most sources continued to use Wood's placement in ''Dichelostemma'', including the ''Flora of North America'', which however noted that it was "quite distinct from other species in the genus" and that it was perhaps "best treated as its own genus". In 2017, restoration of ''Dipterostemon'' as a monotypic genus was proposed. This has been accepted by sources such as

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

and the Jepson Flora Project.

Subspecies

Three subspecies are accepted: *''Dipterostemon capitatus'' subsp. ''capitatus'' *''Dipterostemon capitatus'' subsp. ''lacuna-vernalis'' (L.W.Lenz) R.E.Preston *''Dipterostemon capitatus'' subsp. ''pauciflorus'' (Torr.) R.E.Preston (common name - desert hyacinthMojave Desert Wildflowers, Pam MacKay, 2nd ed., 2013, )

Uses

Corms have been gathered by Native Americans in California, parts of the Great Basin, and the Southwest. These corms were an important starch source in their diet. California tribes dug and continue to dig the corms before flowering, during flowering, or after seeding depending on the tribe and individual family. Traditional gathering sites were visited annually, and there were gathering tracts with different kinds of corms and bulbs owned and maintained by particular families. Corms are eaten by animals such as black bears,

mule deer The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer. Unlike the related whit ...

, non-native wild

pig The pig (''Sus domesticus''), also called swine (: swine) or hog, is an omnivorous, domesticated, even-toed, hoofed mammal. It is named the domestic pig when distinguishing it from other members of the genus '' Sus''. Some authorities cons ...

rabbit Rabbits are small mammals in the family Leporidae (which also includes the hares), which is in the order Lagomorpha (which also includes pikas). They are familiar throughout the world as a small herbivore, a prey animal, a domesticated ...

s, and

pocket gopher Pocket gophers, commonly referred to simply as gophers, are burrowing rodents of the family Geomyidae. The roughly 41 speciesSearch results for "Geomyidae" on thASM Mammal Diversity Database are all endemic to North and Central America. They ar ...

s. As some of the corms are eaten, others are dispersed. The animals detach the cormlets, which aerates the soil, prepares the seedbed, thins the plant population, and leaves some cormlets behind. Once separated, corms may take less time to reach flowering size. Although slow to flowering starting from seeds, it is sometimes used in horticulture. The flowers mix well in native beds, especially when contrasted against other California native species such as California poppies (''

Eschscholzia californica ''Eschscholzia californica'', the California poppy, golden poppy, Mexican poppy, California sunlight or cup of gold, is a species of flowering plant in the family Papaveraceae, native to the United States and Mexico. It is cultivated as an orn ...

''). With patience and proper care, these plants can become quite dramatic come spring.

Management

Indigenous people had several different types of management activities to ensure future corm production at gathering sites: #breaking off cormlets from the harvested parent corms and replanting them #sparing whole plants #harvesting the corms after plants have gone to seed and dumping the seeds in the hole #burning areas #irrigation Periodic digging and thinning of the corms or separating the cormlets, and replanting them may have enhanced plant numbers and densities. Digging corms acts as a form of tillage, which will increase the size of the gathering tract, aerate the soil, lower weed competition, and prepare the seedbed to increase seed germination rates. ''Dipterostemon capitatus'' populations require periodic disturbance to maintain and increase their populations; therefore, indigenous harvesting regimes may help maintain populations. Populations that become overcrowded and show reduced vigor can be divided and separated.

Propagation

Seeds sown in the fall usually readily germinate and do not need special treatment. If planting seeds, they will take several years to reach flowering size. Propagation by corms is much easier.

References

External links