14. Saxifraga tricuspidata Rotbøll, Skr. Kiøbenhavnske Selsk. Laerd. Elsk. 10: 446. 1770.
Prickly saxifrage, saxifrage trois dents
Plants loosely mat-forming, (stems trailing), not stoloniferous, with elongate caudex or rhizomatous. Leaves cauline, (marcescent, crowded proximally); petiole absent; blade (often reddish), linear to cuneate, 1-3-lobed or -toothed apically (distal cauline unlobed), rarely all unlobed, (lobes long spinose-mucronate), 5-20 mm, leathery, margins entire, softly glandular-ciliate, (nonsecreting hydathodes present adaxially), apex acute, long spinose-mucronate, surfaces glabrous. Inflorescences 3-10-flowered cymes, 4-10(-24) cm, white to sparsely pink- to purple-tipped stipitate-glandular; bracts sessile. Flowers: sepals erect to ascending, (sometimes purplish), triangular-ovate, margins f glandular-ciliate, surfaces white to purple-tipped stipitate-glandular; petals white to cream, proximally to distally yellow-, orange-, and red-spotted, elliptic to ovate, 4-7 mm, much longer than sepals; ovary superior. 2n = 26.
Flowering late spring-summer. Open sandy, gravelly, or rocky sites, forest openings, grassy slopes, rocky ridges, stony tundra; 0-3000 m; Greenland; Alta., B.C., Man., Nfld. and Labr. (Labr.), N.W.T., Nunavut, Ont., Que., Sask., Yukon; Alaska , Mich.
The rare, entire-leaved form of Saxifraga tricuspidata can be confused with S. bronchialis; it has glandular-ciliate margins instead of stiffly hooked-ciliate ones.