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Rayjacksonia aurea
Rayjacksonia aurea is a species of flowering plant in the family Asteraceae known by the common names Houston tansyaster[2] and Houston camphor daisy. It is endemic to Texas in the United States, where it is known only from the Houston area. It is limited to Galveston and Harris Counties.[1][3] DescriptionThis species is an annual herb which generally remains small in its native habitat but in cultivation may be much larger.[3] It grows from a taproot. The small leaves are linear or lance-shaped and just a few millimeters wide. The flower heads contain several yellow ray florets which may reach nearly a centimeter in length.[4] The plant has a scent like camphor. Flowering occurs in October and November.[3] Distribution and habitatThis plant grows on the Texas coastal prairie, especially on Mima mounds and in open areas such as fields and pastures.[5] It prefers sandy soils or loams, and typically grows in areas that are seasonally wet or are poorly drained.[5] The plant may occur with other rare local endemics, such as Texas windmill grass and prairie dawn.[5] ConservationThe species is currently classified as imperiled, and fewer than 20 populations remain.[3] The species and its habitat are threatened by development and expansion of the Houston metropolitan area, as well as from competition from woody vegetation and non-native grasses.[1][5] References
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