Willows

Willows are weeds of national significance. They were used widely in the 1950s to control erosion on river banks, but have had disastrous effects on streambanks and river (or riparian) environments. Willows can:

• cause channel diversions or bank erosion
• 'choke' streams and change flooding patterns
• cause changes to water quality
• affect native fish habitat.

Willows can grow from seed, but they also reproduce by cuttings. When a branch or twig breaks off a tree, it can take root and form a new plant. This allows willows to spread down a river as quickly as it takes their branches to float downstream. They can out-compete native vegetation, eventually forcing native plants out of an area.

Some 32 willow species or hybrids live in Australia, but the problem is greatest in NSW, Victoria and Tasmania. In NSW, willow control projects are running in a wide variety of places.