In polar view, ridges low, gently-rounded, or semi-circular; ridges straight, 11 to 17 in number Ephedra torreyana type

Ephedra torreyana
S. Wats., Ephedraceae
CN: Jointfir or Mormon Tea
SIZE: Polar axis 45 µm equatorial diameter 20 µm
RANGE: Southwestern Colorado to Nevada, south to western Texas, Arizona and Chihuahua.
NOTES: Can be destinguistd from E. trifurca by its less numerous and sharper ridges.

Ephedra torreyana S. Wats., Coll. Arizona. Ephedraceae.