I have been planting on the banks of the Waimata River for 15 years now, hoping the work I do will make a difference and provide a platform that others can follow. After many losses of species that were the wrong tree in the wrong place, I have found what can cope with the water flow and ground subsidence and I thought I was starting to get it right.
I am a great believer in flax fans taken from an older plant and planted into silt. I cut the flax back to three fans —mama, papa and pepi. They are genetically older than plants from a seed and they can cope with the grass competition, meaning less work. These fans will grow a root that is as long as the fan itself and I believed in time they would hold the lower banks of the river. The flax needs to be able to withstand tonnes of water flowing over them and be resilient enough to recover after flood events.
We have endured multiple floods with water and silt pouring over the flax, burying them many times. All they need in order to survive is one baby fan poking out of the silt and they will recover and stand up tall within six months. This has been marvellous and I was always excited to tell others of my great achievements.
That was until Cyclone Gabrielle came past. Cyclone Hale and the previous wet weather were not a problem. The flax and cabbage trees were all standing proud under Kenways Bridge, and then oh my, what a different event Cyclone Gabrielle was. The water roared and the slash came, adding weight to the already stressed banks and vegetation. The banks themselves couldn’t cope and the land gave way and took the plantings with it.
There was crashing and banging as the logs fell against the bridge, slips were moving on the hills like avalanches and slash piled up behind the willows, poplars and natives, putting tonnes of force against trunks. Then, when the trees were released, the land they stood on disappeared into the river and out to sea or on to Tairāwhiti beaches.
So now the clean-up, and where do we start? I have identified species of plants that have withstood the river’s fury and the layers of silt. Flax is still a go where the land has held but I am reluctant to plant too low down on the river banks even though I know that the bare soil will be eroded. Manuka, kanuka, cabbage trees, tree ponga and ferns, totara and kahikatea have been OK if they were older than seven years. These trees are not as susceptible to goat, deer and wandering stock browsing which is also a consideration for restoring riverbanks.
Poplar, willows and funnily enough liquidambars are all coping with the silt loading. I am not advocating the planting of willows again as in the past we know the problems that were caused, but as a holder of the banks they can’t be beaten, so some poplar planting has been undertaken to hold key sites. The pittosporum, coprosma, karamu, putaputaweta, lancewood, ribbonwood and many other regenerating species have all been suffocated under the silt — if they are still standing at all— leaving the banks a bit bare and disappointing me as a grower and planter. But we can only work with nature as she lets us.
Pictures of our riverbanks covered in natives are few and far between. I have one historical picture (black and white) of the Waimata River that I keep on my wall as inspiration. The species that were on the river are hard to identify from the picture but time will tell.
A friend commented on one of my river posts, “Never ever give up!” so on the King’s Birthday Weekend, in the rain, some friends answered my call for help and we replanted using the five resilient species — cabbage trees, manuka, kanuka, totara, kahikatea and flax. This time I am planting higher on the banks but I am certain in a few years time I will be brave and start to plant lower.
A massive thank you to the Waimata Catchment Group for providing the plants and a massive thank you to my friends, old and new, who came out to awhi te awa.
