Ivesia paniculata
Encyclopedia
Ivesia paniculata is a species of flowering plant in the rose family
known by the common name Ash Creek mousetail, or Ash Creek ivesia. It is endemic to the Modoc Plateau
of Lassen
and Modoc Counties
in the northeastern corner of California
, where it is known only from the vicinity of Ash Valley. It was first described in 1981. This is a small perennial herb of sage scrub on volcanic soils and rocky slopes. It forms a matted clump from a woody caudex
and produces leaves and stems which lie on the ground or are somewhat erect. Each leaf is about 2 to 5 centimeters long and is made up of rows of many tiny, lobed, pink-edged green leaflets, densely coated in short white hairs. The leaflets overlap such that each leaf is cylindrical. The mostly naked pinkish stems bear inflorescence
s of hairy clusters of flowers. Each flower is about half a centimeter wide and has hairy pink-edged greenish sepal
s and tiny pale yellow petals. There are five stamen
s and a few pistils
.
Rosaceae
Rosaceae are a medium-sized family of flowering plants, including about 2830 species in 95 genera. The name is derived from the type genus Rosa. Among the largest genera are Alchemilla , Sorbus , Crataegus , Cotoneaster , and Rubus...
known by the common name Ash Creek mousetail, or Ash Creek ivesia. It is endemic to the Modoc Plateau
Modoc Plateau
The Modoc Plateau lies in the northeast corner of California as well as parts of Oregon and Nevada. It is a mile-high expanse of lava flows with cinder cones, juniper flats, pine forests, and seasonal lakes. The plateau is thought to have been formed approximately 25 million years ago...
of Lassen
Lassen County, California
Lassen County is a county located in the northeastern portion of the U.S. state of California. As of the 2010 census, the population was 34,895, up from 33,828 at the 2000 census...
and Modoc Counties
Modoc County, California
Modoc County is a county located in the far northeast corner of the U.S. state of California, bounded by the state of Oregon to the north and the state of Nevada to the east. As of the 2010 census, its population was 9,686, up from 9,449 at the 2000 census. The current county seat is Alturas, the...
in the northeastern corner of 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 only from the vicinity of Ash Valley. It was first described in 1981. This is a small perennial herb of sage scrub on volcanic soils and rocky slopes. It forms a matted clump from a woody caudex
Caudex
A caudex is a form of stem morphology appearing as a thickened, short, perennial stem that is either underground or near ground level . It may be swollen for the purpose of water storage, especially in xerophytes...
and produces leaves and stems which lie on the ground or are somewhat erect. Each leaf is about 2 to 5 centimeters long and is made up of rows of many tiny, lobed, pink-edged green leaflets, densely coated in short white hairs. The leaflets overlap such that each leaf is cylindrical. The mostly naked pinkish stems bear 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...
s of hairy clusters of flowers. Each flower is about half a centimeter wide and has hairy pink-edged greenish sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s and tiny pale yellow petals. There are five stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s and a few pistils
Gynoecium
Gynoecium is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves which evolved to form a closed structure containing the ovules...
.