Flora of New Zealand Series

silver wattle

Shrub to large tree; twigs ribbed, densely puberulent. Lvs 2-pinnate, alternate, densely puberulent on rachis and sparsely hairy on pinnules; pinnae in (6)-10-21 pairs; pinnules in 25-40-(50) pairs, fairly close set, glaucous, narrow-oblong, obtuse or subacute, entire, 2-4-(7) × c. 0.75 mm; petiole (5)-10-20 mm long; stipules inconspicuous; solitary glands present between each pair of pinnae, usually except basal pair. Infl. of numerous, many-flowered, medium yellow, globose heads arranged in axillary, compound racemes ± = lvs. Fls 5-merous, sessile. Pod glabrous, ± straight, 50-100 × 8-12 mm; aril scarcely folded, thickened to one side of seed.

N.: locally common throughout but not recorded for Taranaki; S.: locally common to abundant in dry N. and E. areas especially riverbeds of N. Canterbury and Marlborough; St.: Halfmoon Bay.

S.E. Australia, Tasmania 1870

Waste places, scrubland, riverbeds.

FL Jul-Sep.

In many areas silver wattle forms dense stands by suckering. The lvs of seedlings usually differ markedly from those of mature trees in being less glaucous, having fewer pinnae and fewer and larger pinnules. However, the distribution of glands and stem hairiness is the same as that of mature trees. Some flowering specimens have lf forms similar to those of seedlings; again stem hairs and gland distribution distinguish these specimens from related N.Z. naturalised spp. Pinnules are close set when compared with the widely spaced arrangement in R. decurrens. Silver wattle has been previously known in N.Z. as Acacia dealbata and A. decurrens var. dealbata.