Alien Invasives

10 October 2016

Other names

Brittle Willow (English)

Invasive status

NEMBA Category 2

Description

The Crack Willow is a medium-sized to large deciduous tree, which grows rapidly up to 20 metres tall, with a trunk up to 1 metre in diameter. It is often multi-trunked with an irregular and often leaning crown. The bark is dark grey-brown and coarsely fissured in older trees. The lanceolate leaves are bright green with a finely serrated margin. Leaves are very finely hairy at first in spring, but soon become hairless. The flowers are produced in catkins in early spring and are dioecious (with male and female catkins on separate trees). In late spring fruit capsules release numerous small cotton-tufted seeds. They are easily distributed by wind and moving water, and germinate immediately after soil contact.

Originally from

Europe and Western Asia

Where is it a problem?

All over South Africa especially along rivers

How does it spread?

Seed and fragmented branches that root readily

Why is it a problem?

Grows rapidly along river banks, shading large areas and often causing erosion. Its ability to easily break branches which root readily means it can colonise large areas rapidly.

Planting alternatives

River Bushwillow (Combretum erythrophyllum)

Uses

Ornamental