Within the state of Utah are seven species of Geranium, two of which are annual. The nature of the caudex and the growth habit have been used to separate the perennial species. These characters are inadequate for separating the species. Better morphological characters, keys, and descriptions are presented.
Nebeker, Glen T.
"Revision of the plant genus Geranium in Utah,"
Great Basin Naturalist: Vol. 34
, Article 8.
Available at: http://scholarsarchive.byu.edu/gbn/vol34/iss4/8