Do all of the seeds used in the reforestation project come from Abel Tasman National Park? If not, where else are they sourced from? Also, how do you decide which species to plant in each location?
Yes, all the plants used in reforestation projects in the ATNP are ecosourced. Ecosourcing means that seeds are taken from native plants in the same area as the restoration project. Ecosourcing is often used in restoration projects because locally sourced plants are thought to be more likely to survive than those from further away. This is because native species are often better adapted to their local conditions. See more on ecosourcing at: http://www.naturespace.org.nz/resource-centre/ecosourcing-seeds-and-plants
In some rare instances, local seed sources for a particular species have become threatened or may even be extinct in an area. For example, some of the last remaining pingao in Golden Bay is on Farewell Spit. This means that most pingao planted in Golden Bay comes from the Farewell Spit source population.
When there is a limited population of a specific plant it can mean that it has an extremely limited gene pool. In these situations it may be a good idea to supplement the seed collected from your local plants with seeds from further away, or collect seed from the nearest known healthy population. By adding plants from other places, and expanding the gene pool, you are able to future proof your planting against environmental changes or diseases that could otherwise threaten the new planting.
The species chosen to be planted at restoration sites are plants which would have grown in that location naturally - before man-made changes occurred, such as fires, land clearance, drainage, the introduction of pest animals that eat native plants, and the introduction of weeds that often out-compete native plants.
We know what was previously growing at the site by researching historic maps and descriptions, and using pollen records from the time before humans arrived.
Rebecca, DOC Partnerships Ranger