Eriogonum jamesii and Eriogonum arcuatum can be confused and, in fact, James Reveal, Eriogonum expert, indicates in his treatment of Eriogonum in the Flora of North America, "Eriogonum arcuatum has long been included under E. jamesii" In his key to Eriogonum, Reveal gives them separate species status.  Stanley Welsh, Utah flora expert, disagrees with Reveal: "The concept of E. jamesii is restricted [in FNA] to those [plants] with white to cream colored flowers.  Use of flower color as the basis for segregation seems to this writer to be superfluous, and [therefore I maintain] the traditional application of the name E. jamesii".

The two plants are nearly identical in almost all of their characteristics and measurements; they are best separated, according to Reveal, by their flower color: yellow for E. arcuatum and white to cream for E. jamesii.  In addition, although the upper side of the leaves of both species may be densely wooly-hairy, E. jamesii can be "thinly hairy or even glabrous". 

Note that the E. jamesii plant shown on this page is growing in a warm, moist environment and the E. arcuatum on the linked page is growing in a hot, dry environment.  Thus the considerable difference in their appearance.  In similar environments, the two plants are difficult to tell apart.

This and the next photograph show Eriogonum jamesii's shiny, glabrous leaves and pale cream/yellow flowers --  characteristics that separate it from the otherwise very similar E. arcuatum.

Range map © John Kartesz,
Floristic Synthesis of North America

State Color Key

Species present in state and native
Species present in state and exotic
Species not present in state

County Color Key

Species present and not rare
Species present and rare
Species extirpated (historic)
Species extinct
Species noxious
Species exotic and present
Native species, but adventive in state
Eradicated
Questionable presence

Range map for Eriogonum jamesii