Isocoma rusbyi, Rusby's Goldenbush
Scientific Name: Isocoma rusbyi
Common Name: Rusby's Goldenbush
Also called: Goldenbush
Family: Asteraceae, Sunflower Family
Synonyms: (Aplopappus drummondii, Haplopappus rusbyi)
Size: Up to 3 feet.
Growth Form: Subshrub; woody, glabrous, light colored.
Leaves: Light green; narrowly lanceolate, some elliptic; up to 2 inches in length, margins entire.
Flower Color: Yellow disk flowers only; numerous flower heads on tips of stems, 20 or more florets per head. Fruit is an achene.
Flowering Season: July to November
Elevation: 2,000 to 7,000 feet.
Habitat Preferences: Lower and upper deserts, pinyon-juniper, chaparral and Creosote Bush communities, washes, rocky, sandy and gravelly areas
Recorded Range: Distribution limited in the United States to the southwestern states of AZ, CO, NM and UT. Found in central and northern AZ, southwest CO, northwest NM and southeast UT. Native also to northwest Mexico.
North America & US County Distribution Map for Isocoma rusbyi.
U.S. Weed Information: No data available.
Invasive/Noxious Weed Information: No data available.
Wetland Indicator: No data available.
Threatened/Endangered Information: No data available.
Comments: Rusby's Goldenbush is a fall blooming yellow daisy formerly included in the genus Haplopappus called Rabbitbrush and Goldenweed. This species and several others were reclassified to Isocoma and other genera.
It attracts insects and butterflies, is toxic to livestock, and is superficially similar in appearance to other Goldenbush species, particularly Alkali Goldenbush, Isocoma acradenia. In Southwest Desert Flora, also see Southern Goldenbush, Isocoma pluriflora and Burroweed, Isocoma tenuisecta.
Named in honor of Henry Hurd Rusby, (1885-1928), economic botanist at The New York Botanical Garden.