Eriophyllum confertiflorum - Golden Yarrow

Eriophyllum confertiflorum (DC.) A. Gray (Golden Yarrow) is a small shrub/woody perennial herb with lobed, often trifid (3-pointed) leaves.   The stems and leaves are usually tomentose, attaining a height between 2 and 7 dm.   The leaves are 1-5 cm long, obovate in outline, deeply 3-5-lobed, with leaf margins rolled under, becoming glabrous above with age.   The inflorescence consists of 10-30+ densely clustered heads on peduncles <10 cm long.   The flowers are deep yellow, with each head containing 10-35 disk flowers, with the corolla lobes 2-3 mm long.   It is a member of the Asteraceae (Sunflower family).

There are two varieties of Eriophyllum confertiflorum in Ventura County: confertiflorum and tanacetiflorum, with the later being rare.   Var. confertiflorum possesses 10-30+ heads with ray flower ligules 2-5 mm long while var. tanacetiflorum possesses fewer heads with ray flower ligules 4-5 mm long.   Furthermore, the peduncle of var. tanacetiflorum is longer, and generally extends well above the body of the plant when compared to var. confertiflorum.

Eriophyllum confertiflorum (DC.) A. Gray var. confertiflorum ranges from northern California to Baja California and is a common plant in chaparral, Coastal Sage Scrub, and Coast Live Oak Woodland vegetation in Ventura County.   It blooms for a very long time, starting in the early spring.   It is common in Ventura County and elsewhere in California.

Eriophyllum confertiflorum var. confertiflorum - Golden Yarrow


Eriophyllum confertiflorum var. tanacetiflorum (E. Greene) Jepson (Tansyleaf Golden Yarrow) is very similar to var. confertiflorum, but has more flowers per head but more heads per inflorescence, and the clusters are more loosely arranged.   This variety ranges from northern California to northern Ventura County, with the Ventura County occurrences representing a significant range extention and is disjunct from most populations.   It is found in oak woodland, Pinyon-Juniper Woodland, and Great Basin Sagebrush Scrub plant communities from between 600 and 800 m above sea level.   Eriophyllum confertiflorum var. tanacetiflorum has been placed on the California Native Plant Society's List 4, Plants of Limited Distribution, and is rare in Ventura County, known from the Cuyama Badlands and Upper Sespe Creek in northern Ventura County.

Eriophyllum confertiflorum var. tanacetiflorum - Tansyleaf Golden Yarrow



All photos copyrighted by David L. Magney 2003-2007