Potentilla argentea L.
(C.J.W., D.R.G.)
hoary cinquefoil
Ascending to erect perennial herb up to c. 50 cm tall, with branches arising from a stout, woody stock; stems ± woody, brown to reddish purple, white-tomentose. Lvs both basal and cauline; petiole up to 20-(55) mm long, pilose; blade reniform, palmate; leaflets usually 5, oblanceolate to obovate, sessile, (5)-8-16-(24) × 3-15 mm, dark green to greyish and usually glabrate to sparsely hairy, rarely moderately hairy above, densely white- to grey-tomentose below; margins recurved, with 1-3 pairs of teeth in upper 1/2, sometimes ± pinnatifid; upper cauline lvs becoming ± sessile, smaller and often finally 3-fid; stipules lanceolate, white-tomentose below, acuminate and sometimes with 1-(2) teeth. Fls in diffuse, terminal cymes, 5-merous. Epicalyx segments subulate, 1.5-3 mm long, acute, entire. Sepals ovate-triangular, = or slightly > epicalyx segments, sparsely to densely tomentose, connate at base. Petals broadly obovate, 2-4-(5) mm long, yellow, very shallowly emarginate or rounded. Style filiform-conic. Achenes ± smooth or slightly reticulate, not winged, 0.7-1 mm long.
S.: S. Canterbury and Otago (mostly MacKenzie Basin and adjacent Waitaki R., C. Otago, and Queenstown district).
Europe, Asia 1935
Dry, stony terraces and hillsides with sparse vegetation, riverbeds and waste places, occasionally persisting in irrigated pasture.
FL Nov-Mar FT Dec-Apr.
P. argentea is somewhat variable and is sometimes split into a number of segregate spp. Most N.Z. specimens seem close to P. argentea sens. strict. Apomicts and polyploids are included in the complex, but the cytology and breeding systems of N.Z. plants are not known.
