Two views of Tiritiri, from opposite ends of the island, with the position of Bush One marked.
By the time that farming ceased on Tiritiri in 1971 native flora on the island was largely confined to pohutukawa around the coastal cliffs, and some remnant areas of forest in a few of the valleys. Alan Esler, a DSIR botanist, visited Tiritiri on behalf of the Hauraki Gulf Maritime Park. He looked at the vegetation in each valley and for ease of identification of the forest remnant areas he numbered them in an anti-clockwise direction starting with Bush One in the valley to the south of the Pa.
Cattle and sheep had been free to browse in the forest remnants, and there was little in the way of understorey plants. In his report on Tiritiri, Esler concluded “It is clear that the forest would clothe most of the island quite rapidly in the absence of sheep and cattle. Replanting would be quite unnecessary . . . natural reafforestation should be considered.”
Mark first visited Tiritiri in 1975 as part of a 3rd year university project to study the regeneration that was beginning to occur within the forest remnants. There were a lot of tree seedlings becoming established and it was clear that given enough time the bush areas would recover. However there were some constraints on what could happen naturally even in the recovering bush areas. For instance, there were only two Puriri trees surviving on the island, both in Bush one. Without some intervention this species would be very slow to spread into other areas.
Outside of the bush areas, the obvious result of removing farm animals was a huge growth of dense grass. A few years later there had been little encroachment into the grassed areas from the remnant forest. Bracken fern was spreading, the grass had become impenetrable and the population of kiore (the Polynesian rat) had snowballed. The dense grass and bracken prevented the growth of tree seedlings and any that did grow were devoured by kiore.
In 1978 botany lecturer Neil Mitchell joined John Craig’s research team on Tiritiri. Together they pushed the idea of replanting the island, and of creating an ‘Open Sanctuary’ – a place where endangered birds could be safe, and where the public could view the birds. This proposal met with some resistance at first, but was eventually accepted and a plant nursery built in 1983.
A suggestion that the seedlings be grown in ‘root trainers’ was adopted. These, at the time, new products encouraged long fibrous roots in the young plants, but also, because they were smaller and lighter than the usual black polythene bags, a tray of them could be carried by almost anyone. This opened up the possibility of involving the public and led to the creation of the ‘Spade Brigade’ of volunteer planters.
The method of calculating how big the nursery needed to be is a great illustration of university thinking in action. Knowing that planting could only be carried out in winter, the number of boat trips was calculated allowing for 50 percent bad weather cancelations. A fit person can plant about eight trees per hour but in each boat load only half would be able bodied (The frail, elderly and children being the other half). Calculating trees per boatload x boatloads per winter they estimated 30,000 trees would be planted per year, and the nursery built to produce them.
Between 1984 and 1994 in excess of 231,000 trees were planted by a huge number of volunteers.
The planting programme was very successful and young tree deaths were less than expected, resulting in some areas now requiring thinning and the removal of trees to create light-wells.
The cache is hidden on the Kawerau Track boardwalk in an area that, to us, will always be Bush One. Walking the boardwalk is a somewhat surreal experience for us. There are so many land-mark trees that we still remember well, but everything is approached in a different direction to how we used to walk through the valley.
When placed this cache carries with it a very special trackable: The curse of the FTF Geocoin #8. This comes with some special obligations on the FTF, so please read about the geocoin before heading out to FTF this cache.