Tree lupin (Lupinus arboreus) is a fast-growing shrub that thrives in harsh coastal conditions, producing long-lived seeds that spread rapidly. In the Flaxbourne River mouth, it has become a major problem, forming dense stands that overshadow native vegetation and alter soil fertility by fixing nitrogen. This shift encourages more weeds and exotic grasses, while its thick cover prevents shorebirds like dotterels and wrybills from nesting safely.
Though complete control in the river is unrealistic, reducing lupin around the river mouth and keeping on top of new seedlings is critical to protect the coastline. Working with landowners, contractors, and volunteers, we’re aiming to contain lupin spread before it colonises fragile dune habitats.
