Photo: Bobbie Carroll
Spinifex is our most common and effective native dune grass. Photo: Bobbie Carroll
Sand dunes form the buffer between land and sea. To function effectively the foredunes must be well vegetated with native sand-binding grasses such as Spinifex and Pingao, giving way to plants such as Knobbly Clubrush, Muhlenbeckia and Tauhinu and then larger shrubs and trees as the dunes stabilise landwards.
Piha Coastcare has taken an active part in re-vegetating damaged foredunes at Piha, particularly by planting Spinifex and Pingao grasses and working with Council to provide accessways across the dunes. Trampling kills dune plants, and by using access ways, visitors reach the beach without damaging the plants.
Contrary to popular belief, a well cared for dune with a vegetated toe ensures that the dune doesn’t grow too high. As soon as wind-blown sand reaches a Spinifex dune, the wind speed decreases and its sand load drops near the beach rather than on the top of the dune.