Willow weed is a sprawling summer annual found in moist, well-aerated soils. Highly invasive, it can smother large areas of both newly-sown and established pastures. It is generally unpalatable to stock, but deaths have been recorded overseas.
Willow weed produces a large volume of seeds which remain viable for some time, and it can also reproduce from small pieces of broken stem.
Optimal control is achieved by spraying at seedling stage (less than 75mm high). Established plants are poorly controlled.