Crack willow
Salix × fragilis · Salicaceae · also Brittle willow
A broad, fast-growing willow to 25 m whose brittle twigs snap with an audible crack and root wherever they wash up, so a single tree can colonise a whole river. In Britain it is a familiar pollarded riverside tree. In New Zealand and Australia it chokes waterways, diverts flow, drops leaves that deoxygenate streams and displaces native riparian trees: it is banned from sale, propagation and distribution under the NZ National Pest Plant Accord 2020 and is a Weed of National Significance declared in every Australian state.
Where it stands
Native
This tree evolved here, and local wildlife depends on it.
- 🇹🇷 Türkiye · WCVP records the hybrid as native to Türkiyesource
Care
Do not plant in New Zealand or Australia; in its naturalised European range pollard every 5 to 15 years in winter to keep it safe. Control is by cut-and-paint or stem injection of herbicide, leaving dead trees standing a year before removal so banks do not collapse; broken twigs re-root, so bag and remove them. Replace with local native riparian species.
Benefits
Good for