Sunday, January 10, 2016

Visiting Hawaii--The Ever-Changing Big Island

Odd things remind one of the changes that time brings.
coast of Hawaii
Coast of the Big Island, Hawai'i
I spent 11 months in Hawaii in 1981-2, doing research on ant-plant interactions. (Because Hawaii has no native ants, ant-related characteristics of plants should be reduced or lacking. My specialty was extrafloral nectaries, glands that produce sugar-water on leaves and other places that ants might encounter. I did find reduced frequency of the nectaries on native Hawaiian plants).

In 2012 we returned for a visit. I knew that time had passed, and that, for example, Hilo now had a Walmart. I also knew that the active volcano, Kilauea, had been erupting more or less continuously since I was there. But I didn't think much of it.

In 1981 we lived in Hilo and on workdays I drove up Route 11, Volcano Road, to Hawaii Volcanoes National Park and spent the days studying native plants. At the end of my workday, I would drive down Chain of Craters Road, with spectacular vistas out to sea along relatively new lava, and then turn toward the ocean and drop quickly down the cliffs (palis) to sea level.
pali with lava flows, Hawaii
Pali with lava flows
At the base of the pali, I turned with the ocean to my right and followed the coast road, driving first to Kalapana, then inland to Pahoa and then home to Hilo.

You can't do that today.

lava blocking road
Lava flow blocking road

The lava from the eruptions of the last 30 years covers the coast road that I so loved with several feet of rock. The Park and the county of Hawaii rebuilt that road after previous eruptions and no doubt will do so again, some time in the future, but for now it is blocked. And it has been for years, it is just that I had not been there.

Hawaii coast
The swimming beach that was in this area is deeply buried, the
coast now 100 yards farther out to sea. 
Likewise, Kalapana, a small town south of Hilo, had a small but lovely swimming beach, one of just a few on the rather wild east coast of the Big Island. The lava not only covered the beach, it buried it in 60 feet of new rock, and destroyed more than 100 houses in and around Kalapana. The destruction was national news when it happened, and the changes are old news today.

I'm from Ohio and Colorado in the center of the U.S., where the land rarely changes and certainly where molten rock doesn't cover everything 30' deep in a decade.

The photo below is of Wahaula Heiau, an Hawai'ian archaeological site--a temple complex--which was very important in Hawaiian history. It was on the coast, along the coast road, not far south of Kalapana. It was buried by Kilauea's lava in the 1980s. I have visited Wahaula Heiau, but I cannot visit it again. It is gone (well, buried deeply).


Wahaula Hiaeu 1982
Wahaula Heiau in 1982

Change happens.

Sometimes slowly, so you don't notice it accumulating, sometimes while you are elsewhere or just not paying attention.

Then you do notice, and wow! for better and worse, things have changed.

One lesson from this is: Go! Go see places, be there. Change will happen, maybe not driven by a volcanic eruption, but what you can experience now will presently not be available.

A second lesson from the Big Island is adaptability. The native plants of Hawaii have been enduring volcanic eruptions since the first seed arrived on the island chain, long before the Big Island emerged from the ocean.

We teach that soil-building is slow. If a flood or avalanche scrapes a place in Colorado or Ohio down to naked rock, it will take hundreds of years, probably more like a thousand years, for natural processes to build soil on that site so that the plants that were there before the disaster can grow there again.

So how are the photos below possible?

To the right of the sign is a tree about as tall as the sign, growing on 40-year-old lava. It is not waiting for soil formation. (And there are more little trees fon the lava beyond it--magnify the photo).


tree on lava flow, Hawaii

Or the ferns in this a'a lava. (Two main kinds of lava, a'a with lots of little rocks, and pahoihoi, the big smooth rocks).

ferns in lava


And a second tree, same species as the one by the 1974 sign, ohia lehua, Metrosideros polymorpha, one of Hawaii's two dominant native trees, growing out of the lava, about 2' high and flowering. 



Another example, the shrub ohelo, a native Hawaiian cranberry, Vaccinium reticulatum, growing out of lava and ash. And flowering.

ohelo on lava, Hawaii


It isn't magic: these plants grow in spots where nutrients and water accumulate. However, in the places on the mainland where I worked, half a century of soil building certainly would not produce the conditions for trees and shrubs to flourish. What you find after 50 years would be lichens and maybe a few mosses clinging to the rock surface, certainly not trees and shrubs in flower. 

forest and lava, Hawaii

Areas that the volcano misses--the lava somehow goes around--are very much more complex and diverse: note the forest beyond the lava flow above. Only a few of Hawaii's native plants can grow on new lava. 

But we can take a lesson of hope from the plants of the Big Island: even a disaster the size of 10' of molten rock pouring over the vegetation is just a moment in time.  Because it is a recurring disaster, the plants are adapted to it and recolonize rapidly. A new forest will appear.

And the coast, although different, is still magnificent. 


coast of Hawaii
Coast at base of pali, Hawaii Volcanoes National Park

coast at Kalapana, Big Island, Hawaii
Coast at Kalapana, Big Island, Hawaii


Comments and corrections welcome.

Kathy Keeler
More at awanderingbotanist.com





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