Grusonia grahamii

Engelmann. 1856. Proceedings of the American Academy of Arts and Sciences 3: 304 (as grahami)

What is Grusonia grahamii?

Grusonia grahamii is a Chihuahuan Desert dog cholla that grows on sandy, gravelly bajadas and flats under 1500 m.

Details

G. grahamii forms mats of stem segments to 100+ cm across. The cladodes are 3-7 x 1.5-3.5 cm with narrow tubercles that are 10-15 mm long. Areoles are 3 mm in diameter with white to yellowish wool. There are (6)8-15 spines per areole mostly in the distal areoles. The longest spine is 3-5.5 cm. The major 2-3 abaxial spines are erect and often red-brown. The major 2-4 adaxial spines are divergent and ascending and often rich red-brown, +/- terete. Marginal spines are deflexed and whitened, angular-flattened to subterete; the longest central abaxial spine is usually brownish with whitish wavy lines. Glochids may reach 6 mm and ca be very numerous. The most recent treatment is in Club Chollas of the Big Bend 3.0 (see Appendix E). G. grahamii has tuberous roots and it is tetraploid.

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