''Encelia resinifera'', the sticky brittlebush, is a

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

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 ...

Distribution

The species is found at elevations between in the states of

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

and

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

, in the

Southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...

. It grows in soils derived from

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

Description

''Encelia resinifera'' is a shrub ranging in height from . The trunk, which becomes fissured with age, supports slender stems. The

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

, which range between 10 and 25 mm in length, are ovate or lanceolate and are usually pointed at the tips. The yellow

flowerheads 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 ...

are borne singly, appearing between May and July (late fall to mid-summer) in their native range. These have 8-13

ray floret 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 ...

Subspecies

Two subspecies have been identified: *''Encelia resinifera'' subsp. ''resinifera'' — button brittlebush. *''Encelia resinifera'' subsp. ''tenuifolia'' C.Clark — found in the

Grand Canyon The Grand Canyon (, yuf-x-yav, Wi:kaʼi:la, , Southern Paiute language: Paxa’uipi, ) is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is long, up to wide and attains a depth of over a m ...

area. It has both leaves and ray laminae with a length that is more than three times their width.

Taxonomy

''Encelia resinifera'' was originally described as a variety of '' Encelia frutescens'' (''Encelia frutescens'' var. ''resinosa'') by M.E.Jones in 1913. In 1998 it was reclassified as a distinct species by

Curtis Clark Curtis Clark (born 23 April 1950) is a jazz pianist from Chicago, United States. Clark was born in Chicago, Illinois in 1950, but moved to Los Angeles where he spent his student years and started composing and playing the piano. After Clark grad ...

.Clark, Curtis. 1998. Aliso 17(2): 201

References

{{Taxonbar, from=Q5375332 resinifera Flora of the Colorado Plateau and Canyonlands region Flora of Arizona Flora of Utah Endemic flora of the United States Plants described in 1913 Flora without expected TNC conservation status