Flora of New Zealand Series

tortured willow

Tree to 3-8-(13) m high; bark fissured. Smaller branches and shoots strongly contorted, not pendulous. Ultimate stems and shoots rather slender and pendulous, green to dark reddish, flexible, shining, hairy at first, becoming glabrous or almost so. Buds brown, becoming glabrous. Petiole c. 5 mm long. Lamina 2-16 × 0.5-2.5 cm, linear-lanceolate, oblong-lanceolate, or oblanceolate, quickly glabrous, ± shining above, glandular-serrulate; apex acute, mucronate or acuminate. Stipules twisted, sometimes 0. Catkins ♀, produced with or after lvs, 1-1.5 cm long, narrowly cylindric, ± spreading; rachis villous. Bracts 2-2.5 mm long, oblong-lanceolate, green, hairy at base; apex rounded or obtuse. Gland 1, minute or 0. Ovary sessile, glabrous.

N.: Opotiki, Rotorua; S.: Westport, Canterbury (Waimakariri R.).

E. Siberia, N. China, Korea 1983

Riverbeds, lakesides, swamp margins.

FL Sep.

Although tortured willow is mainly considered as a decorative tree for gardens, it is sometimes planted along riverbeds and lakesides where detached shoots quickly root in moist ground. Wild plants are also often found on the outskirts of towns and cities near municipal rubbish dumps. It is almost certainly wild in many places in N.Z. as well as those recorded above. Tortured willow or corkscrew willow is a freak ♀ clone of S. matsudana called `Tortuosa'; it is one of the most common and widely planted willows in parks and gardens in recent times and is now grown in all settled areas of the country. Its twisted branches and shoots are very characteristic and are almost unique among willows, wild or cultivated, in N.Z. Very rarely a male clone of what may be a S. fragilis and S. matsudana   cv. 'Tortuosa' cross is cultivated and it is also has a twisted branch system. One specimen (CHR 143983, Kainga, N. Canterbury, Healy 64/213, 24.9.1964) represents this plant; it has ♂ catkins 2-3.5 cm long, in the range of S. matsudana rather than S. fragilis. The tree from which the specimen was collected may have been spontaneous.

In the last decade there has been considerable interest in more typical S. matsudana. It has been widely planted in and around many towns and cities, particularly in the North Id, for soil conservation purposes and as a shelter and street tree. It is most probably becoming naturalised. A female clone with erect main branches and pendulous branchlets is often used, and a feature of the mature trees is the mass of short rootlets formed between the bark ridges on the main trunk.

Considerable work has been carried out recently at the Soil Conservation Centre, D.S.I.R., Aokautere, near Palmerston North, raising hybrids between S. alba and S. matsudana. The main purpose has been to produce a range of clones for soil conservation planting. A secondary purpose is to produce trees of suitably erect habit for shelter belts and screens which will form acceptable substitutes for Lombardy poplars affected by rust fungi. Several clones have been released and are now abundant in many parts of N.Z.