Packera bernardina
Encyclopedia
Packera bernardina is a rare species of flowering plant in the aster family
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 San Bernardino ragwort. It is endemic to the San Bernardino Mountains
San Bernardino Mountains
The San Bernardino Mountains are a short transverse mountain range north and east of San Bernardino in Southern California in the United States. The mountains run for approximately 60 miles east-west on the southern edge of the Mojave Desert in southwestern San Bernardino County, north of the...

 of southern 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 from about twenty occurrences. It grows in mountain pine forests and the unique pebble plain habitat type of the local region.

It is a perennial herb growing 30 to 50 centimeters in maximum height from a branching 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 a rosette of basal leaves; several rosettes, each with a stem, may be clustered together. The spatula-shaped leaves have small squared oval blades with toothed edges which are borne on the ends of long petioles
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...

. Smaller, simpler leaves occur farther up the stem. The leaves are coated in a very short layer of woolly 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...

 contains several flower heads
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....

, each lined with hairy 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...

. The head contains many golden yellow disc florets and generally either 8 or 13 yellow ray florets each up to a centimeter long. The fruit is an achene
Achene
An achene is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent...

 with a body about a millimeter long tipped with a pappus
Pappus (flower structure)
The pappus is the modified calyx, the part of an individual disk, ray or ligule floret surrounding the base of the corolla, in flower heads of the plant family Asteraceae. The pappus may be composed of bristles , awns, scales, or may be absent. In some species, the pappus is too small to see...

of 3 or 4 millimeters.

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