The Hawai'i That Had Never Been: A Mountain That is Younger Than Me, Mauna Ulu

Mauna Ulu, a mountain that originated between 1969 and 1974

So much of geology is incremental. A rock slides from a cliff top, a river carries sand grains downstream, a glacier slowly pushes debris down a mountain canyon. Each of these minor events add up to major changes to a landscape over millions of years: mountains disappear, lakes and seas fill with sediment, canyon gorges are carved. But to a human observer, the changes are invisible. We simply don't live long enough to see the changes that take place in geologic time.

Hawai'i, especially the Big Island, is different. The entire island is less than a million years old, not even 1/4,000th the age of the planet. Because the island sits atop a hot spot, volcanism is a near constant activity, and volcanism leads to major and rapid changes to the landscape. In this current blog series, we've been talking about the "Hawai'i That Was", the environment that existed prior to the arrival of the Europeans, and before the arrival of the Polynesians. But when we look at volcanic activity at Kilauea on the Big Island, we are looking at landscapes that have never existed before. They are new lands.

That's not to say that much is destroyed in the making of new landscapes. The basaltic lava that emanates from the vents along the flank of Kilauea's east rift does a lot of destruction as it flows towards the sea. Take a look at the mound of lava in the picture above. It's a lava tree, formed when lava flowed past a living tree, and congealed around the burning trunk. The level of the lava dropped, but not the solid material around the former tree. The original Hawaiian thought these to be the lithified bodies of humans (although the one above looks much more like a cat).   

My last post on the subject was a discussion of how kipukas preserve a bit of the world that was, prior to the eruption. I said that we visited two of them, but I later remembered that we explored two others as well. It was a trail near Chain of Craters Road that took in two volcanoes, Pu'u Huluhulu, and Mauna Ulu (this is a different Pu'u Huluhulu than the one on Saddle Road).

About 500 years ago, a mildly explosive basalt eruption produced a cinder cone now called Pu'u Huluhulu ("shaggy hill"). Over time, intense weathering of the basalt cinders produced a rich soil that allowed the growth of a rainforest. The forest covered the surrounding landscape too, but that changed not long ago. In 1969 eruptions began along the rift zone that produced lava flows for five years, the longest sustained eruption ever recorded (this record as since been broken by the current Pu'u O'o eruption that started in 1983 and is continuing today).

The lava flows filled around half of the craters along Chain of Craters Road, and covered the road too. The flows piled up against Pu'u Huluhulu as well, but weren't thick enough to overwhelm the hill and the rainforest that covered it. The forest survived as a kipuka. The trail climbs to the summit of Pu'u Huluhulu, and provides what is said to be a spectacular view of Mauna Loa, Kilauea, and Mauna Kea. I'd love to show pictures of the view, but one doesn't get to control the weather when traveling to the islands. We spent much of the hike in a rainstorm with a low cloud deck.

But there was something that we could see: a new mountain. Mauna Ulu is a 400 foot high shield volcano that came into existence while I was starting high school. It's hard to comprehend the pace of geologic change when it is incremental and slow, but it is also sometimes hard to believe how fast things can happen too. There are at least four mountains in the United States that didn't exist when I was born in 1957: Pu'u Pua'i in Kilauea Iki, Pu'u O'o, Mauna Ulu (below), and...the dome in the crater of Mt. St. Helens in Washington state! Rapid geologic change is not confined to the Big Island of Hawai'i...

The hike to the top of Pu'u Huluhulu is mostly level, with a steep climb at the end of a 1.25 mile trail from just off Chain of Craters Road in Hawai'i Volcanoes National Park. Don't miss it if you are ever in the park, and do it on a sunny day. I'd like to see the view!

The Hawai'i That Was: A Tale of Two Kipukas, and Thoughts on the Rarest Plants in the World

Thousands of years ago there was an eruption at Humu'ula Saddle, the broad wide pass between Mauna Loa and Mauna Kea on the Big Island of Hawai'i. The eruption was mildly explosive, so the resulting landform took shape as a cinder cone. At the time, it was a barren peak amidst a forest of native Koa trees. As time went on, soils developed on the cinder cone, and the forest expanded to cover the hill. Much later the situation was reversed because extensive sheets of basalt flowed from Mauna Loa, most recently in 1843 and 1935. They covered the entire saddle area and decimated the Koa forest. Except for the lone cinder cone. A small remnant of the ancient forest survived.

The hill, called Pu'u Huluhulu ("hairy" or "furry" hill) is a stark example of a kipuka, an island of sorts in the middle of lava flows that preserves a portion of the original pre-flow surface and the plants and animals that lived there. The Google image above shows just how isolated the cinder cone is. If you are looking for the "Hawai'i That Was", a kipuka is a good place to start. They are like museums of what once was, but they are far more than that. In preserving the flora and fauna, they provide the genetic material that will eventually repopulate the areas of devastation.

Edge of Pu'u Huluhulu, where plants start to recolonize the lava flows.

There are hundreds of kipukas spread across the Big Island on Mauna Loa and Kilauea. We explored two of them on our recent exploration of the islands: Pu'u Huluhulu at Saddle Road, and Kipuka Puaulu in Hawai'i Volcanoes National Park.  Because it is a hill at the boundary between Hawaii's two largest volcanoes, Pu'u Huluhulu offers dramatic views. It is also a bit schizophrenic: it is composed of cinders from the "plumbing" system of Mauna Kea, but was later intruded by dikes of basalt from Mauna Loa.

Mauna Kea from the top of Pu'u Huluhulu

The forest of Pu'u Huluhulu may have escaped the destruction of lava flows, but it has not escaped alteration by humans. The northwest flank was quarried for cinders in the past, and is still barren on that side (although geologists appreciate the exposure of dikes and cinder layers). Cattle, goats and sheep have grazed the hill at various times, although a fence now keeps them out (as long as hikers close the gates). Several short trails, though steep and rocky in a few spots, provide access to much of the kipuka, and the site is recognized as a hot spot for viewing rare native birds.

Kipuka Puaulu, the "Bird Kipuka", at Hawai'i Volcanoes National Park (forested area in center of picture).

At Kipuka Puaulu (or Kipukapuaulu) in Hawaiian Volcanoes National Park the situation is a bit different. For one, it is about ten times larger than Pu'u Huluhulu, covering about a square mile. It's also more of a depression than a hill. About 600 years ago, a lava flow from Mauna Loa overwhelmed the forest of mature Koa and Ohi'a trees, but left a fragment of the woodland sitting on 8,600 year old lava unscathed. Over the years the kipuka was occasionally mantled with ash from the eruptions of nearby Kilauea, but the forest persisted, in part because the ash produced thick moist soils. Today, the kipuka contains one of the most diverse collections of native flora on the Big Island. A beautiful and serene one-mile trail winds through the unique preserve. A Hawaiian elder calls it a "Residence of Godly Existences".

It wouldn't be quite correct to describe Kipukapuaulu as an untouched pristine environment. Cattle were released on the islands in the late 1700's, and pigs and goats moved in as well. The natural flora of the kipuka had no defenses against the aggressive grazers, and by the early 1900's, the kipuka was a park-like grassland shaded only by the "grandfather trees", the older Koa and Ohi'a trees that the cattle couldn't reach. A park sounds pleasant enough, but the trees couldn't reproduce (the saplings were quickly eaten), and the diverse understory of shrubs and perennials had been replaced by alien grasses (below).

Source: National Park Service (https://www.nps.gov/havo/planyourvisit/upload/Kipukapuaulu_Trail_Guide.pdf)

The potential value of the kipuka as a preserve of rare native species was recognized surprisingly early by botanists, who arranged for the removal of cattle in 1928, and the removal of goats and pigs by 1968 (a fence surrounds the kipuka). Volunteers removed the worst of the invasive weeds and grasses, and seeds of native plants lying dormant in the soils started sprouting. In other cases the native species were planted by hand. After a few decades, the kipuka is returning to a condition that is at least comparable to its natural primeval state.

Hau kuahiwi (Hibiscadelphus giffardianus), once extinct except for a few seeds

Have you ever wondered about the identity of the rarest plant in the world? We recently had a story about a single plant of Franciscan Manzanita in San Francisco, discovered at an intersection that was being repaved. How about a plant with no living shoots or branches? One of the strangest stories I've run across regarding Kipukapuaulu is that of the small Hibiscus tree called Hau Kuahiwi (Hibiscadelphus giffardianus). A botanist named Joseph Rock (with that name he should have been a geologist) discovered the sole remaining specimen of the plant on planet Earth in Kipukapuaulu in 1911 (the cows had not quite finished it off). The one plant died in 1930, but a local resident managed to collect enough seeds to get a few sprouts going, and so the plant survives in captivity, so to speak. Around 200 have been planted in the kipuka that was its ancestral home (as well as the adjacent kipuka, for insurance from possible future lava flows).

The kipuka came under protection pretty much in the nick of time. Some of the "grandfather trees" that shade the preserve have been dying off in recent years (like the trees in the picture above). On species, the Ohi'a tree (Metrosideros polymorpha) is one of the most extraordinary of the native trees in Hawai'i. The Ohi'a thrives in a greater range of environments than pretty much any tree on the planet, being found in places as diverse as new lava flows, desert slopes, and alpine ridges. They can appear as small shrubs or as huge rainforest canopy trees nearly a hundred feet tall. The Ohi'a trees in the kipuka are dying, perhaps of old age, a newly spreading fungal disease, or because of a series of droughts in recent years (maybe all three). With the diversity of plants now in place, one would hope the kipuka would be able to adapt to the loss of the old trees.

 A few steps off the trail is an intriguing opening in the ground. It is a lava tube, part of the plumbing system of basaltic lava flows. Because it has existed for more than 8,000 years, it is one of relatively few that has some species of cave-dwelling organisms (including the first one discovered in Hawaii). Like the rest of the kipuka, the cave was heavily impacted (in this case by graffiti artists, vandalism and trash), but visitors are now encouraged to leave the cave alone.

The preponderance of native plant species attracts the native bird species to the kipuka, and they can commonly be seen flitting about in the forest canopy. They thrive here for two reasons: at 4,000 feet, they are above the mosquito zone, so are protected from transmitted diseases, and mongooses have not crossed the barren lava flows to prey on the birds. They are frustratingly difficult to photograph, and I am actually cheating here by showing a picture of an Apapane from nearby at the park visitor center.

The bird below is often seen in Kipukapuaulu, but it is not actually a native. It is a Kalij Pheasant, a 1962 import from southern Asia. There is some concern about the effects they might be having on the vegetation.

To the average visitor the islands, the kipukas are a little-known aspect of Hawaiian geology and biology, but they are an important link to the past, and an important repository of the island's genetic history. If you ever visit, set aside some time for an exploration.

View from the forest on Pu'u Huluhulu towards extensive Mauna Loa lava flows.

Much of my information in this post is drawn from the Kipukapuaulu Trail Guide, written by Tim Tunison and Andrea Kaawaloa-Okita, and published by the Hawai'i Natural History Association. Additional information was gleaned from the book Hawai'is Native Plants by Dr. Bruce Bohm.

Dispatches from the Road: Kipukapuaulu, a Residence of Godly Existences

As noted previously, I'm actually not on the road anymore in Hawaii, but since I had the idea for this post while I was there, I'm still calling it a dispatch. And actually, the first two pictures are aren't from my recent trip either, but they illustrate very nicely the idea of a kipuka. The picture above shows a number of cinder cones in the high summit valley of Haleakala on the island of Maui. If you look closely at the rough, blocky a'a flow below the closest cone, you can see an odd smooth area that I have enlarged below. The lava flowed around the small area of older rock, and that is what a kipuka is: an area of land that is completely surrounded by a lava flow.

If the land surface pictured above had not been at 8,000 or 9,000 feet, one could imagine that a forest growing within the kipuka might have survived the volcanic eruption and lava flow, and in the aftermath would be isolated from any surrounding forest tracts.

That's what happened at Hawaiian Volcanoes National Park on the Big Island of Hawai'i. About 600 years ago, a lava flow from Mauna Loa overwhelmed the forest of mature Koa and Ohi'a trees, but left a fragment of the woodland sitting on lavas 8,600 years old unscathed. The kipuka was often mantled with ash from the eruptions of nearby Kilauea, but the forest persisted. Today, the kipuka contains one of the most diverse collections of native flora on the Big Island. A beautiful and serene one-mile trail winds through the unique preserve. The place is called Kipukapuaulu, or the Bird Kipuka. A Hawaiian elder calls it a "Residence of Godly Existences".

It wouldn't be quite correct to describe Kipukapuaulu as an untouched pristine environment. At one time it was, but cattle were released on the islands in the late 1700's, and pigs and goats moved in as well. The natural flora of the kipuka had no defenses against the aggressive grazers, and by the early 1900's, the kipuka was a park-like grassland shaded by the "grandfather trees", the older Koa and Ohi'a trees that the cattle couldn't reach. A park sounds pleasant enough, but the trees couldn't reproduce (the saplings were quickly eaten), and the diverse understory of shrubs and perennials had been replaced by alien grasses.

The potential value of the kipuka as a possible preserve of rare native species was recognized surprisingly early by botanists, who arranged for the removal of cattle in 1928, and the removal of goats and pigs in 1968 (a fence surrounds the kipuka). Volunteers have removed some of the worst of the invasive weeds and grasses, and seeds lying dormant in the soils started sprouting. In other cases, native species were planted. After a few decades, the kipuka is returning to a condition that is comparable to its natural state.

One of the strangest stories I've run across regarding Kipukapuaulu is that of the small tree called hau kuahiwi (Hibiscadelphus giffardianus). A botanist named Joseph Rock (shouldn't he have been a geologist?) discovered the sole remaining specimen of the plant on planet Earth in Kipukapuaulu in 1911 (the cows had not quite finished it off). He managed to collect enough seeds to get a few sprouts going, and so the plant survives in captivity, so to speak. A couple have been planted in the kipuka that was its ancestral home.

The kipuka came under protection sort of in the nick of time. Some of the "grandfather trees" that shade the preserve have been dying off in recent years (like the Ohi'a tree in the picture above). Ohi'a trees (Metrosideros polymorpha) are one of the most extraordinary of the native trees in Hawai'i. The thrive in a greater range of environments than pretty much any tree on the planet, being found in places as diverse as new lava flows, desert slopes, and alpine ridges. They can appear as small shrubs or as huge rainforest canopy trees a hundred feet tall. The trees in the kipuka may be dying of old age, or because of a series of droughts in recent years, but new Ohi'a trees will be able to grow to replace them now.

A few steps off the trail is an intriguing opening in the ground. It is a lava tube, part of the plumbing system of basaltic lava flows. Because it has existed for more than 8,000 years, it is one of relatively few that has some species of cave-dwelling organisms (including the first one discovered in Hawaii). Like the rest of the kipuka, the cave was heavily impacted (in this case by graffiti artists, vandalism and trash), but visitors are now encouraged to leave the cave alone.

The preponderance of native plant species attracts the native bird species to the kipuka, and they can commonly be seen flitting about in the forest canopy. They are frustratingly difficult to photograph, mind you, and I am actually cheating here by showing a picture of an Apanane from a 2004 visit.

The bird below is often seen in Kipukapuaulu, but it is not actually a native. It is a Kalij Pheasant, a 1962 import from southern Asia. There is some concern about the effects they might be having on the vegetation. You can gauge the level of interest by biologists by the fact that this one had a leg tag. There is a hen hidden in the leaves to the right.

Kipukapuaulu is a fascinating and peaceful place to visit. The nature trail is well-marked, and much of my information in this post is drawn from the Kipukapuaulu Trail Guide, written by Tim Tunison and Andrea Kaawaloa-Okita, and published by the Hawai'i Natural History Association. Additional information was gleaned from the book Hawai'is Native Plants by Dr. Bruce Bohm.

Dispatches from the Road: Excuse me, there's a Kao trying to get into your Kipuka Pu'u Huluhulu...

It's hard to imagine a more spectacular setting than Saddle Road Summit on the Big Island of Hawai'i. Two of the world's largest volcanoes, Mauna Kea and Mauna Loa, overlap at an elevation of almost 7,000 feet. In the middle of the broad pass, with expansive views of both volcanoes, there is one of the most extraordinary sights of all the islands: Pu'u Huluhulu. The name means "shaggy hill". It's a small knob, a minor cinder cone lying between two giants, but it tells a fascinating story. The cinder cone erupted several thousand years ago, and has since been surrounded by barren basalt flows, most recently in the 1930s. These isolated areas surrounded by fresh lava flows are called kipukas.
On islands that have been ravaged by invasive species the way Hawai'i has, kipukas serve as islands within islands. They can preserve a native landscape that has disappeared from most of the rest of the islands. At Pu'u Huluhulu, the slopes preserve a Koa tree forest environment that once covered most of Mauna Kea, but which was decimated by logging and grazing over the last 150 years. If and when we decide to change our land-use practices on the islands, a kipuka like this one can be the source of native species that could eventually lead to the reforestation of the mountains.

Koa trees, like those seen above on the trail around Pu'u Huluhulu, once grew in abundance on the islands, reaching upwards of a hundred feet tall, and trunks wide enough to fashion canoes. Most of the "grandfather" trees have been cut down, so a place like this, with a Koa forest environment, is all the more valuable.

One cannot mistake this place as a pristine environment, though. The area was grazed heavily over the years and invasive weeds arrived on boots, and on the fur of goats, cows and pigs. The pigs and goats were especially destructive of the understory shrubs. What has changed is the growing recognition of the value of such places. A fence has been constructed to keep out the goats and pigs, and volunteers have been weeding out the invasive plant species, and planting, or encouraging the growth of dormant seeds of the native understory shrubs and perennials. They're doing a good job. The native vegetation attracts native bird and insect species, and Pu'u Huluhulu is often a good place to see the native Amakihi, Apanane, Io (Hawaiian hawk), Pueo (Hawaiian owl), Nene (the Hawaiian goose), I'iwi and other unique birds. We heard, but didn't see any close enough to photograph on this trip, but I'll be back!

We did see a rather incongruous sight, though: a herd of goats wandering across the barren lava fields (that's the "kao" of the blog title today). They know very well what lies across the fence, and they literally hang around the gateways in the fencing, hoping for a chance to get into the kipuka and do their thing, which is eating and eating. When they say "close the gates", please do it! There is grazing land across the highway for the goats.

If you have old memories of Saddle Road as a hellish, dangerous winding mountain road, or if you visit for the first time and read that the road is not for the faint of heart, the situation (for better or worse in the philosophical sense) has changed. The road has been repaved and engineered, and is a pleasant drive, if it isn't raining or foggy. Some people miss the wildness of the old route, which was pretty unnerving when I followed it for the first time. The expansive views, especially on the western slope on clear days, are stunning. It's a purely Hawaiian experience, but not a Hawai'i stereotype. There really isn't any place like this in the world.

Next time: a different kipuka...

Pu'u O'o: the Big Picture

More details to follow about the Pu'u O'o flow, but going through my pictures, I discovered that I had a single shot that included the entire flow from start to finish: the copter was flying east of the flow, so Pu'u O'o is where the massive steam plume is rising on the right, while the Kalapana ocean entry is visible on the far left. The series of cliffs and rises are the palis, or fault scarps generated by slippage of the volcanoes towards the sea along major fault systems. Smaller steam plumes are vents and windows over the lava tube system, and the occasional surface flow. Note especially the pattern of forest islands, called kipuka. They are important biological refugia where some native species are protected from invasive predator species.