Check out this video to see what’s happening under the canopy up on Reotahi/Mt Aubrey.
Out of sight, underneath the canopy of our incredible forests, there is a serious and growing problem. Wild ginger is quietly eating away at the integrity of our forests from the inside out.
Wild ginger is a very real and present danger to the Heads environment; it has very shade tolerant seedlings that are being spread through the our forests by birds, and these isolated seedlings increase in density until with the entire forest floor is covered by the dense, deep, beds of rhizomes, preventing all other native regeneration. This means that as the existing native trees die, they will not replaced and the forest canopy will collapse.
One example where this is already happening is the northern face of Reotahi – Mt Aubrey. Looking up at this maunga you would be forgiven for thinking it is reasonably healthy and resilient, but once you take a look inside it is a different story. In large areas the entire sub-canopy is now dense beds of ginger, and in other areas canopy collapse has already begun. Unless we take some action we will eventually be left with a very different landscape, one with only wild ginger and very little else covering the slopes of all of our precious maunga.
As always though, if we recognise the need to act, it is possible to prevent this weedy future. One fantastic volunteer, Marc Lawrence, has spent hundreds of hours clearing wild ginger on Reotahi/Mt Aubrey, and has made huge progress on some of the worst areas, clearing fields of dense ginger (check out the video link if you haven’t already: Helping to stop the rot on Reotahi). Just imagine what we could achieve as a whole community, with everyone tackling even just the small amount in their own backyard, or taking care of the bush over the back fence of their property. Wild Ginger plants growing out in the open in the full sun produce the most seed, so every flowering plant removed makes a huge difference to the rate of spread.
Wild ginger is easy to kill. The soft stems can be cut above the pink “collar” at base with secateaurs or a knife, and the stump treated with a mixture of 1g metsulfuron/1L water. The Weed Action Community Store has this herbicide, and trigger sprayers for easy application, available for free right now. Treating it now when flowering will stop another season of seed being produced and spread. It is also easiest to spot at this time of year when it has bright yellow spikes of flowers.
More info and photos on the wild ginger ‘Dirty Dozen’ page here