Ionactis alpina
Encyclopedia
Ionactis alpina is a species of aster
known by the common name lava aster. It is native to western North America from California
to Montana
, where it grows in dry areas.
and fibrous root system. It produces a short, mostly erect, hairy stem to 12 centimeters in maximum height. Most of the small leaves are on the lower part of the stem. They are up to about a centimeter long, oval to lance-shaped and pointed, somewhat stiff and coated in hairs.
The inflorescence
bears solitary flower heads
with purple-green phyllaries
, thin purple ray florets and long yellow disc florets. The fruit is a hairy achene
.
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...
known by the common name lava aster. It is native to western North America from 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...
to Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
, where it grows in dry areas.
Description
Ionactis alpina is a perennial herb growing from a caudexCaudex
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 fibrous root system. It produces a short, mostly erect, hairy stem to 12 centimeters in maximum height. Most of the small leaves are on the lower part of the stem. They are up to about a centimeter long, oval to lance-shaped and pointed, somewhat stiff and coated in hairs.
The 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...
bears solitary flower heads
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....
with purple-green phyllaries
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...
, thin purple ray florets and long yellow disc florets. The fruit is a hairy achene
Achene
An achene is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent...
.