- Reduce wind erosion.
- Build up sand dunes which reduce wave erosion.
- Speed recovery of dunes after storms.
- Grow in the hostile coastal environment.
- Prevent direct wave erosion.
- Withstand excessive damage from people, stock or vehicles.
- Cope with mowing.
- Tolerate introduction of unsuitable exotic plants.
Pingao (foreground) and spinifex are able to tolerate the harsh front dune environment and are important sand-binding plants.
In many coastal areas, introduced species have been planted to stabilise or beautify dunes.
Unfortunately these species aren't as effective at dune protection as native plants, and they can sometimes make erosion worse.
Many introduced species have also become a problem as they can over-run large areas and threaten native species.
Some of the problem species are agapanthus, exotic iceplant, purple groundsel, prickly pear, daisies, acacia, boneseed, coastal banksia, freesias, kikuyu grass and acacia.
Purple groundsel.Exotic ice plant.
Help stop the spread of pest plants
Many pest plants are garden escapees – you can help by:
- Composting garden waste instead of dumping it onto the dunes
- Removing invasive introduced plants and replacing them with natives.
Contact the Northland Regional Council for removal techniques and suitable replacement plants.
Dunes can be replanted to encourage natural processes, if there's enough space between the beach and buildings or roads.
Replanting can also re-establish important native plants that have become critically rare in some areas – like spinifex and pingao – and restore the natural character and values of an area.
Keep in mind that some areas are naturally unstable and are valued environments just as they are. Before you commit to a project that's trying to address dune stability, take a stroll along the beach and think about the natural coastal processes that are at work.
Northland CoastCare groups carry out dune restoration projects to protect and enhance native vegetation and replant it where necessary.
If you're planning a replanting project, get in touch with the Northland Regional Council for advice and to find out what's going on in your area.