''Senecio hydrophilus'' is a species of flowering plant in the
aster family known by the common names water ragwort
and alkali-marsh ragwort. It is native to western North America from
British Columbia to
California to
Colorado, where it grows in swampy places such as
marshes. It can grow in standing water, including alkaline and salty water. It is a biennial or perennial herb producing a single erect stem or a cluster of a few stems which may exceed one meter in maximum height, at times approaching two meters. The stem is hollow, waxy in texture, and often pale green in color, and it emerges from a small
caudex
A caudex (plural: caudices) of a plant is a stem, but the term is also used to mean a rootstock and particularly a basal stem structure from which new growth arises.pages 456 and 695
In the strict sense of the term, meaning a stem, "caudex" is m ...
. The thick leaves are lance-shaped to oval with smooth or toothed edges, the blades up to 20 centimeters long and borne on
petioles. Smaller leaves occur farther up the stem. The
inflorescence is one or more large, spreading clusters of many
flower heads. They contain many yellowish disc florets at the center and sometimes have small yellow ray florets as well.
References
External links
Jepson Manual TreatmentUSDA Plants ProfileFlora of North AmericaWashington Burke MuseumPhoto gallery
hydrophilus
Flora of Northern America
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