Salix purpurea L.
purple osier
Shrub or small tree to 4-(8) m high with rather smooth trunk; habit rather erect. Shoots slender, greenish or grey-green, sometimes reddish or purplish above when young, glabrous, flexible. Buds glabrous, dark. Lvs mainly alternate, opposite towards shoot apices; petiole usually < 5 mm long. Lamina 2.5-11 × 0.5-2 cm, linear, linear-lanceolate, or oblanceolate, glaucous or glaucescent, especially below, glabrous or sometimes hairy when very young, bitter to taste, finely serrulate or subentire; apex acute. Stipules 0. Catkins usually ♀, rarely ♂, appearing before lvs, erect, narrow-cylindric; rachis villous. ? catkins 1.5-3 cm long. Bracts 0.6-2 mm long, oblong to obovate, black in upper 1/2-3/4, with silky hairs; apex obtuse to rounded. Gland 1, 0.3-0.6 mm long, oblong or ovate-oblong. Stamens 2, but completely fused and appearing as 1; filaments hairy; anthers purplish. ♀ catkins 2-4 cm long, otherwise similar to ♂. Ovary white-sericeous, sessile.
N.: Wairarapa, Palmerston North, Wellington; S.: Christchurch area.
Europe, W. Asia, N. Africa 1968
Streamsides, not common.
FL Sep-Nov.
Purple osier was introduced for riverbank and inland montane soil stabilisation, as well as for basket-making. A vigorous ♀ clone with erect branches called `Booth Willow' is the usual form of purple osier seen in N.Z. S. purpurea is also sometimes cultivated in gardens for its attractive catkins, for which purpose ♂ plants are preferred. A record of S. × rubra Hudson (S. purpurea × S. viminalis) from Canterbury is probably in error for S. purpurea, because this hybrid has lvs of similar shape and colour which are often opposite towards the shoot apices (in N.Z. this character is only found in this sp. and S. × rubra). S. × rubra is a hairier plant, the ♂ fls do not have completely fused filaments and the anthers are yellowish. S. purpurea is unpalatable to stock because of its bitterness and this adds to its usefulness in soil erosion control.
Another hybrid which is sometimes cultivated, and has been reported as wild in the Kingston area, C. Otago, is S. × pontederana Willd. (S. cinerea × S. purpurea). This is quite distinct from S. purpurea and is represented in N.Z. by ♀ plants only. It forms a small to medium-sized tree and has oblong-lanceolate or obovate-lanceolate lvs which are glaucescent below and soon become glabrous. The catkins are more like those of S. cinerea than of S. purpurea, being 2.5-3 cm long and broad-cylindric.
