Tiarella trifoliata
Sp. Pl. 1: 406. 1753 ,.
Flowering stems 10–70 cm
Distribution
Alta., B.C., Alaska, Calif., Idaho, Mont., Oreg., Wash.
Discussion
Varieties 3 (3 in the flora).
Varieties of Tiarella trifoliata have overlapping ranges and differ from each other in leaf form and marginal dissection. Their floral features are stable throughout. They were previously suspected of hybridizing when sympatric. They are differentiated along elevational gradients and often remain distinct in sympatric populations.
Selected References
None.
Lower Taxa
Key
1 | Basal leaves usually simple; cauline leaves rarely trifoliolate, shallowly to deeply lobed, leaflets sessile. | Tiarella trifoliata var. unifoliata |
1 | Basal leaves 3-foliolate; cauline leaves 3-foliolate; leaflets deeply lobed, petiolulate | > 2 |
2 | Leaflet lobes to 1/2 length of leaflet, distal segments not laciniate. | Tiarella trifoliata var. trifoliata |
2 | Leaflet lobes more than 1/2 length of leaflet, distal segments laciniate. | Tiarella trifoliata var. laciniata |