Ochiai pass

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A picture of Ochiai pass taken December last year.  Even though it says Ochiai pass, it took nearly half an hour of driving from Ochiai hamlet.  And the road was terrible, narrow and full of potholes, not the kind I would want to drive again, though I probably will go there again anyways.  The "pass" itself was very beautiful, and combined with a fine weather it was one of the best moments of my time in Iya so far.

I visited the pass partially because on the mountaineering guide book said the pass is a field of thatch grass, and I was looking for thatch fields.  Unfortunately, the pass was actually covered with dwarf bamboos, and thatch was growing on the gaps of bamboos.

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In this picture you can see the bamboos better.  I later learned that there has been repeated studies on the plant species composition of this pass since 1960s, and it clearly records the shift from thatch to bamboos.  In the past, people burned the field every few years to keep the pass open, and to collect edible plants and medicines.  Now a days, the constant wind blowing over the mountains and the covering of the ground by bamboos keep the trees from taking over the pass, keeping the pass as a bamboo grassland.  But these bamboos flowers and then dies, all together, every once every half a century or so, and at that point it is likely the field with be succeeded by forest community.  Even now few trees are seen in the fields.

Back in the 1960s somebody has claimed this pass one of the best grassland in the prefecture and potentially a great tourism resource.  Even now, the bamboo field is quite beautiful and can probably attract lots of tourists.  But what will it be like in the future?

Standing tree

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A single standing tree in middle of the thatch field.  Oddly picturesque scene.  It would be a good place for birds to perch on.  Once the thatches are removed, the field will be very open and visible from above.  Maybe a bird of prey will perch on this tree to look for its prey.  When I look closely the tree has several holes.  Perhaps a woodpecker pecked on the tree to look for insects.

In a human-controlled environment such as cedar plantations, dead trees are usually not left standing.  Such trees would be removed to make room for living trees.  But a tree like that has its roles in the ecosystem.  As we Chiiori tries to manage the thatch field, if we are also going to value nature we would have to think about what to do with trees such as this one.  I imagine they burn down fairly easily....

My job here in Chiiori is to gather thatch for the roof.  To do so, I have to investigate the thatch field.  Chiiori's interest is "how can we maintain the thatch fields so that we can re-thatch the roofs." My interest is "how can I use the thatched roofs to maintain this ecosystem of the thatch fields."

The thatch field, Susuki (Miscanthus sinensis) dominated grassland, is an ecosystem that requires regular disturbance.  Otherwise the shade-loving plants and trees will take over the field.  In other words, human activity is necessary for these grasslands to remain.

So, now that the snow has melted and I can go up there again, my job has turned into managing the mowing of these grass so they will have plenty of sunlight to grow again.  After the snow, most of the susuki has fallen to the ground.  But some are still standing and not only do they make shades over other plants, those still standing but old thatch have to be removed before they are harvested next fall for the roof.  Otherwise the old thatch will degrade faster and from there rains start leaking.

The best way to maintain the grassland is with the use of fire.  With fire, even the thatch that has fallen would be removed, ashes fertilize the ground, and overall make the environment favorable for grassland species to grow.  But to use fire in controlled and safe manner, much preparation and labors are needed, which is very difficult to get in Iya.  But even before that, I don't think I can persuade enough people to use fire in the first place....