O Pioneers!

A raw volcano in Hawai‘i will rearrange one’s ideas about Nature, deep and fast. The face of a slow lava flow, with its blast-furnace heat and steel-mill breath, is not a kindly garden of plants and animals nor even a merciless sculptor of landforms; it’s the original real-estate factory. Everything else we know and love is just the patina of age and accumulation on this stuff, this sullenly glowing black ooze that crackles softly and tosses off fairy-dust bursts of glass flakes as its surface cools. At its edges it ignites clumps of grass; you can track the movement by looking for puffs of smoke and brief foot-high flames.
This is primal, a shockingly industrial landscape, and on parts of Hawai‘i it goes on for miles, acres of a‘a, the jumbled blocky rocks, and pahoehoe, the oddly soft-looking ropy rock; the two formed from lava cooled at different rates. It’s black as an asphalt parking lot, and up around the big Kilauea crater it looks like the blasted waste at the end of the world.
We took a guided rainforest tour, and I was grateful for the plant and bird expertise, the loan of walking stick and gaiters, and access to a patch not open to the public. I was just as grateful that someone else did the driving, up over the infamous Saddle Road (not really worse than lots of Marin County) and then over what would’ve been a dirt road but there isn’t any dirt yet. Apparently the best they can do for roads in these parts is to sort of rake the smaller rocks a little closer together. It was bumpity and slow for wheeling or walking, and it looked just as unpromising for growing. But approaching the forest, the vast swaths of cobble looked different, frosted with a baroque silvery crust. And here and there in the waste, damned if there wasn’t something green.
The silver was lichen, colonizing the rainier areas of recent lava flows; and the first green vascular plants to take hold in bits of the barren, exposed, infertile place were ferns. How they shone in that black-and-white rockscape! It was as startling as the switch from sepia Kansas to Technicolor Oz in the Wizard movie. They looked tender, complex, delicate, ostrich-feather elegant.
How many ferns have I killed over the years of bumbly gardening and houseplant ambition? What are these infamously touchy plants doing here where even the locally weedy fountaingrass can’t grow?
It’s nothing new: ferns have been pioneers for millions of years. Their spores blow farther than any seed can, and some species demand little but moisture and a place to hang on. They’ve long been the first complex-plant recolonizers on volcanic islands, and were among the first plants to show up in the devastation zone after the Mt. St. Helens eruption in 1980. That’s just a hint of their history. A “fern spike” — a sharp increase in the number of fern spore fossils — marks the geologic K-T boundary, the delineation between Cretaceous and Tertiary period deposits, the sigil of the catastrophe that drove the great dinosaurs and many of their neighbors to fast extinction.
Ferns had been around much longer than the dinosaurs had, beginning with the Devonian, when they were part of the first wave of land-dwellers ever. With those giant clubmosses and horsetails we see in museum dioramas, they formed the swamps of the Carboniferous period. They had some daunting company there, things like three-foot centipedes. Evidently the affinity continues; one thing we were warned about if we were to take an evening hike on the new lava, the better to see its glow, was the centipedes that come out at night. These, though, are a mere six inches long. If I ever do take that hike it’ll be on stilts and in hipboots.
Hawai‘i has over 150 native ferns, and a handsome tree fern, the hapu‘u, is part of the rainforest understory. A sadly familiar story: the slow-growing hapu‘u is under siege by invasive exotics including Australian tree fern and wild pigs. The pigs knock down a hapu‘u and gnaw out its nutritious pith. As a sidelight, this leaves hollowed half-trunks to catch rain in pools — rare in this porous ground — that foster mosquitoes that carry avian malaria that has wiped out whole native Hawai‘ian bird species.
I wish I could read or write a natural story without that nasty coda. Maybe I should take comfort in anticipating that ferns of some sort will be ready to recolonize whatever waste we leave of the world after our own extinction event.

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