Out here in the Waitakere ranges we’re suffering from a natural disaster. The ground didn’t rise up. We haven’t been flooded. It’s not a fire. Our natural disaster is silent and invisible, a microscopic bug – phytophthora agathidicida – which kills Kauri, the apex of forestry ecosystems in the north of New Zealand.
Once the bug gets into a tree, there is no known cure. Some trees seem to be better at defending themselves than others, but it seems that if a tree cops an infection, its days are numbered. Scientists have been experimenting with sulphite solutions, which may have some ability to improve trees’ defences. But it’s not a cure.
The bug can also survive in dry soil for up to six years. Anything travelling over the soil with the bug in it is likely to pick it up and distribute it. Once the bug comes in contact with water, it can work its way towards kauri roots where it takes hold, multiplies and kills off its host mainly by drawing away nutrients. First it attacks the roots and then it works its way up the tree. More detail on the bug’s life cycle here.
So, human feet are the main distribution vectors, along with pigs’ feet, horses’ feet and bicycle wheels. Hunters are bad because they go both on and off tracks. But they’re also good because they take out pigs, which – like hunters – go everywhere. How many hunters assiduously clean all gear which comes into contact with the ground before departing the hunting ground? A few. More probably do partial cleans, which are about as effective as not cleaning at all: a single pin rick sized piece of infected dirt is enough.
By far the largest proportion of infected trees are on or very near walking tracks. That’s why the iwi Te Kawerau a Maki imposed a rahui on the Waitakere Ranges, where the disease is most prominent, by far.
Auckland Council recently voted down a proposal to follow Kawerau a Maki’s lead and close down the walking tracks. They cited logistical reasons (“too complex, difficult and unenforceable” said Penny Hulse), which seems rather pathetic on the face of it. Instead, Council has been erecting keep-out signs at the front of high risk, high usage tracks. They’ve also been smothering infected areas with gravel.
But plenty of tracks remain open, such as the short, easy, and very popular Arataki Nature Trail, where the disease is rampant. If nothing else, you’d think a few signs (or “interpretation”, as the museological sector calls it) around the infected trees would be useful.
The trouble with leaving those tracks open is that it exposes the trees to further contamination, and – worse – hikers are still likely to pick up and distribute the bug.
In one way, Council has made things worse. It’s not just that they’ve failed to remove the number one cause of the problem (people). It’s also that people assume that if there’s no sign, then there’s no rahui. In some cases, this is benign opportunism. But often, it’s good old fashioned racism.
Some people are complaining that Te Kawerau a Maki has neither the power nor the authority to control where people do or don’t walk. That’s only valid if you firstly: dismiss any respect for the notion of mana whenua, and secondly: put that disrespect ahead of your concern for the kauri trees. In other words, you have to be racist first, and anti-environment second. And here’s me thinking the only people outwardly opposed to the environment were in the White House. Apparently not.
People are also asking: how long is this rahui thingy going to last? That’s a reasonable question. But, since the only plan seems to be to isolate the infected areas and then do everything possible to minimise the impact within those areas, it’s hard to see a short term solution. The bug remains dormant in dry soil for up to six years. So I guess that’s one time frame: assuming we can keep the infected areas dry for six years. Sounds like a bit of a mission.
You know those moments when you worry about the state of the world for our children and grand children? This is that moment. You’re unlikely to live long enough to see the benefits of your actions. Alternatively, you can regard it as an opportunity for generational theft. Keep walking in the Waitakere ranges, and you may well see the total eradication of kauri there, and possibly beyond. Part of the trouble is a tree can be infected for years before the disease is even visible.
There are other opportunities out west. Here’s a list. You’re much better off in the surf at Piha or Karekare. Or you can traverse the otherworldly deserts of Whatipu, or the lakes at Te Henga.
Or you could take your dog for a sprint at Kakamatua. There, your pooch will be scrabbling over the very same beach on which the people of Te Kawerau landed, having crossed the Manukau from Awhitu, after long exile in the Waikato. That exile resulted from musket-armed invasions from northern iwi in the early 19th century. Today, they’re fighting for the very same trees that were already mature and looking down on them when they landed that day in 1835. It’s easy to speculate they felt they’d come to the end of something bad, and the start of something good. If only they knew.
But still, standing there, you can congratulate yourself and your dog for being part of the solution, and you can imagine someone growing up 200 hundred years from now, gazing in wonderment at a forest of healthy kauri. Or not.
PS: Here’s one for those who don’t think in 280 characters.