Packera breweri
Encyclopedia
Packera breweri is a 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 Brewer's ragwort. It is endemic to central 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 occurs in the woodlands and grasslands of the Central Coast Ranges.

It is a biennial or perennial herb producing one erect stem from a fibrous root and 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...

 unit. It grows to a maximum height near one meter or slightly taller. It is mostly hairless, but sometimes has tufts of hairs in the leaf axils. The leaves may be up to 30 centimeters long near the base of the plant, their blades so deeply divided into lobes they appear to have leaflets. Each lobe is edged with teeth. Leaves occurring higher on the stem are smaller with narrower lobes.

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 many 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 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 narrow yellow ray florets each measuring 1 to 2 centimeters 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...

 around a centimeter long, including its 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 bristles.

External links

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