Sarcostemma hirtellum
Encyclopedia
Sarcostemma hirtellum (Rambling Milkweed, Hairy milkweed), is a perennial, vine
-like plant of mid- to lower-elevation desert regions. It is a member of the Asclepiadaceae
family, and the Sarcostemma
genus, the climbing milkweeds. It is found in the southwestern United States
and Northwestern Mexico—in southeastern California
, southern Nevada
, Arizona
, Sonora
, and Baja California
.
Hairy milkweed can be an aggressive, opportunistic species, capable of overtaking a suitable sprouting location and killing the plants it grows upon. If the supporting plants can compete successfully, all of the species continue.
The green vines have few narrow leaves and are themselves photosynthetic. In early- and mid-spring, flower clusters occur in a circular or half-globe cluster of 7 to 13+ florets, with each floret about 3/8 of an inch. The flower clusters are sometimes profuse and therefore noticeable. When the dried seedpods remain months later, after the vines have desiccated, they are the plant identifier.
Another indicator of the plant's presence is the inundation of the supporting species, or multiple species, by quantities of vines.
Vine
A vine in the narrowest sense is the grapevine , but more generally it can refer to any plant with a growth habit of trailing or scandent, that is to say climbing, stems or runners...
-like plant of mid- to lower-elevation desert regions. It is a member of the Asclepiadaceae
Asclepiadaceae
According to APG II, the Asclepiadaceae is a former plant family now treated as a subfamily in the Apocynaceae...
family, and the Sarcostemma
Sarcostemma
Sarcostemma is a genus of at least 35 species of flowering plants in the dogbane family, Apocynaceae. The name is derived from the Greek words σαρκὸς , meaning "flesh," and στέμμα , meaning "garland". Members of the genus are known generally as climbing milkweeds or caustic bushes...
genus, the climbing milkweeds. It is found in the southwestern United States
Southwestern United States
The Southwestern United States is a region defined in different ways by different sources. Broad definitions include nearly a quarter of the United States, including Arizona, California, Colorado, Nevada, New Mexico, Oklahoma, Texas and Utah...
and Northwestern Mexico—in southeastern 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...
, southern Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
, Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
, Sonora
Sonora
Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....
, and Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
.
Hairy milkweed can be an aggressive, opportunistic species, capable of overtaking a suitable sprouting location and killing the plants it grows upon. If the supporting plants can compete successfully, all of the species continue.
The green vines have few narrow leaves and are themselves photosynthetic. In early- and mid-spring, flower clusters occur in a circular or half-globe cluster of 7 to 13+ florets, with each floret about 3/8 of an inch. The flower clusters are sometimes profuse and therefore noticeable. When the dried seedpods remain months later, after the vines have desiccated, they are the plant identifier.
Another indicator of the plant's presence is the inundation of the supporting species, or multiple species, by quantities of vines.