There are lots of pieces of DoC estate where few if any Conservation officers venture. There are so many forests and other interting areas to cover that we can't possibly go to all of them. So, occasionally we pick a piece to look at and send a "taskforce" to check it out.

On this occasion the Taumarunui office expressed a wish to fossick around part of the old Tangarakau Forest Park, just south of Kehuratahi. In case you have a map of the area (and I'm sorry my scanner is not that good), Kehuratahi is on the road (mostly gravel) between Stratford (East of Mt Taranaki) and Taumarunui (halfway between the coast and Lake Taupo). It is the next spot on the map after Whangamomana and before Tahora. So basically, it is way out in the sticks.

TH, our new threatened animal species officer, and I left from Wanganui towing a quad bike on a trailer. We rendezvoused with DC and GR in Stratford. They are Stratford threatened species officer and wild animal control officer respectively. We, unfortunately, all had different schedules and so all ended up driving in separate vehicles, towing quad bikes. It must have seem like a minor invasion force, three DoC vehicles all towing quads.

The piece of DoC land under scrutiny is one of those anomalies within DoC; part of it is currently under a grazing license. That means that it is actively farmed. It really doesn't bring in a great deal of money for DoC (or the farmer), and the surrounding forest is impacted. But at the moment we haven't got the resources to do much else with it, and at least the farmer keeps the worst weeds under control. We parked on said farmer's land, offloaded the quad bikes, stacked them to the gunnels with provisions and research supplies and roared off in three distinct clouds of dust.

The entrance to the valley is really neat; a tunnel dug straight through the hill in typical Tangarakau style. There even were swallows nests attached to protruding boulders in places. These tunnels are not unusual in the area, the one in Tangarakau gorge, closer to Taumarunui, is longer and has cathedral like bracing inside, quite beautiful in a primitive way. Hard to imagine all the effort that went into creating these tunnels and the associated roads to settle forested land in the middle of nowhere.

In the late 1920's returning soldiers were allocated pieces of land as a thank-you for their war efforts. Mostly, these bits of land were in the most inhospitable places that had thus far been left alone because they were not easy to break in or farm. The government of the day saw the returning service people as convenient land-clearance agents. The Bridge to Nowhere leads to another such valley. Most of these areas were abandoned in the early to mid 1940's because life was too hard and too isolated.

By that stage of course, the land had been cleared and farmed for quite a period already and the forest burned off or cleared, generally to the first ridge. If you look carefully at this picture, you can see that the trees on the tops of the hill look quite different to the trees on the slopes. The slopes are regenerating manuka (Leptospermum scoparium), while the ridges are still original forest, mostly.
The trees in the foreground are on the banks of a deeply incised stream. The area is on soft Papa mudstone and streams rapidly, geologically anyway, carve deep channels. In some places, the stream was easily 5 to 7 m below ground-level, and very hard to cross. Also very hard for stock to browse, so you get these fringes of trees along the waterways.

This is what I mean by regeneration forest. Spindly manuka have grown to a height of 4 m or so and provide shelter and a habitat for other, more delicate, species such as ferns and seedlings of the future forest canopy species. Eventually the forest canopy species will overtop the manuka, and the manuka will die back because it is a sun-loving species. However, should there be any gap in the forest, due, for instance, to a tree falling over or a landslide then manuka will rapidly reclaim that area for its own and the regeneration will start anew.

Most of the regenerating forest does not look as lush at this though, because stock keeps grazing underneath the canopy and eating out the palatable species. This photo shows the ragged ends of a hard little fern (Dicksonia lanata) and lots of weeds and grasses on the ground. Not much in the way of interesting species or canopy species manage to escape the voracious teeth of sheep, wild cattle, wild pigs and wild goats. Of course, there are also possums by the thousands.

The herd, of 28 or so, wild cattle limit themselves to pugging up the valley floor (mind you I have known cattle to climb and browse quite steep hills). The sheep penetrate about a 100 m of ridge forest before losing interest. The pigs prefer the lush valleys but can also be found uprooting large areas in the forest. The goats should really be on DoC pay as they keep the ridges completely free of regenerating vegetation. This makes life much easier if you want to go for a walk in the forest. However, it is not very good for the forest structure.