Gone wild
On foxes, flowers, and “invasive species”
This is the Alaskan lupin, Lupinus nootkatensis. She’s native to northern North America. Hardy and cold-tolerant, she grows well across Alaska, and in summer dazzles with brilliant purple blooms.
The Alaskan lupin is a legume. Like all members of the legume family, Lupinus nootkatensis cultivates communities of nitrogen-fixing bacteria on her roots. While Earth’s atmosphere is 70% nitrogen, most of that nitrogen cannot be used by living beings to build themselves, because it’s in a very stable molecular form. “Nitrogen-fixing” bacteria are able to break molecules of nitrogen into ammonia, suitable for use in making amino acids and bases for DNA and RNA, thus allowing the plants to construct new stems, flowers, and seeds. Animals can eat those plants, repurposing that nitrogen to build their own tissues. Our planet’s whole edifice of living creation is build on a foundation of bacteria transforming ubiquitous but useless nitrogen into a version we can use. Legumes have efficiently enlisted those bacteria to their roots, to the benefit of us all.
When soil is too depleted of usable nitrogen, plants won’t grow in it—except for nitrogen-fixers like legumes. And that’s how Lupinus nootkatensis came to Iceland.
Humans from Norway came to Iceland in the ninth century, and then the island was covered in forests. The forests were made of birch and juniper trees, and the humans cut them down. These days, only about 2% of Iceland is covered in trees—and that’s after extensive reforestation efforts.1
When the Vikings were cutting down the junipers to build houses and boats, burn for warmth, and provide land for livestock grazing, they did not know that they wouldn’t grow back like the pines and spruces of Norway they were used to. But junipers are not fast-growing trees like pines. Junipers can live for a millennium or more, but never get taller than a couple of meters high and one meter thick in all that time.
Modern reforestation efforts don’t involve native junipers, either—that would take too long. Instead, Iceland’s forestry department plants stands of pine and spruce trees, like the ones the Vikings left behind in Norway. For Iceland’s harsh climate, pines and spruces are delicate as hothouse flowers, and need to be coddled to have a chance of growing at all. They’re cultivated in greenhouses as seedlings, and then transplanted to grow in the Icelandic soil.
Or at least they are now, after the lupin has been hard at work for the past several decades. Neither junipers nor pines and spruces can grow in soil without free nitrogen, and on its own, Iceland’s soil has very little. Birches fix nitrogen, too, but those were cut down along with the junipers. They’re faster-growing than junipers, but a birch still takes decades to reach maturity. So in 1945 the Alaskan lupin with her pretty purple flowers was introduced to Iceland to stop erosion, save the soil, and allow forests to be grown again.
She was wildly successful.
“When I was a boy, in the 1980s, the lupins hadn’t spread to western Iceland yet,” our tour guide told me.2 The erosion problems Iceland was facing were severe then, with landslides and loss of coastal lands. There weren’t enough plants to hold the sandy soil in place. “Every morning, you’d have to wedge the door open and shovel the sand away from it to be able to open it fully. You’d have to shovel the sand off of the windows so you could see.”
The black sand beach on which we stood was lovely, and now had a relatively fixed coastline. A few bushes grew on the dunes.
“On the little prince’s planet there were—as on all planets—good plants and bad plants,” the aviator narrator of The Little Prince informs us. The Little Prince has come to Earth from his tiny home planet, threatened by deadly baobabs. The baobabs, left unchecked, would grow and spread until they eventually destroyed the planet.
The Little Prince fears for the future of his world. He wishes for a sheep to eat the baobabs. The aviator worries that a sheep that would eat baobabs could kill the Prince’s dearly beloved rose, as well. The ecology of the planet from which the Prince hails is in a precarious balance.
In The Little Prince, neither sheep, nor baobabs, nor roses are native to his world.
Before pines and spruces were introduced to Iceland by the forestry department, there had been a time they lived there before—about one million years ago, according to paleobotanists. Then, the pines and spruces of Iceland were driven to extinction by climate change, the encroaching ice age. The sheets of ice that covered Iceland and killed the pines and spruces a million years ago also connected the island to Greenland and North America. This ice bridge allowed the arctic fox—Iceland’s only land mammal, before the arrival of the Vikings—to migrate there. The little foxes thrived on the icy island, amid its juniper forests and along its coastlines, preying on fish and birds. The foxes adapted when the Vikings came and turned the juniper forests into a moonscape; they survived as the recently-arrived humans hunted them for their fur, and as the introduced lupin spread across Iceland. There were just under 1000 arctic foxes in Iceland in 1970, but there are estimated to be at least 8,000 arctic foxes in Iceland today.
This is down from about 10,000 Icelandic arctic foxes in 2021. They do seem to struggle with the transplanted pine forests.
Lupinus nootkatensis is now listed as an “invasive alien species” in Iceland. Eradication of the Alaskan lupin from Iceland is considered by ecologists to be desirable although probably impossible. The reasons for wishing for the eradication of Lupinus nootkatensis are partly ecological, and partly aesthetic: L. nootkatensis may outcompete native flowers, reducing Iceland’s botanical biodiversity. But also, lush lavender hillsides aren’t bleak and barren. They aren’t evocative of the surface of the moon.3
In preparation for landing on the moon, astronauts on the Apollo missions were first sent to Iceland4. The lifeless rocky landscape would be perfect for helping the astronauts learn how to navigate an environment of geologic, but not biologic features. Today, some of the land the astronauts trained on is teeming with life, because it it colonized with lupins. It is easy to think that a harsh lunar landscape is what Iceland is naturally supposed to have, merely because it’s what it did have after hundreds of years of some of the worst environmental degradation in all of the northern hemisphere.
Neither the aesthetic argument about unearthly barren landscapes nor the ecological argument about competition with native flora are used to argue against the planting of non-native pines and spruces in Iceland. These are described as restoration efforts, returning Iceland to its original pristine state.
But of course this is impossible. Pines are not junipers, and the past is not the present. A real natural ecosystem adapts and changes. It is not a snapshot of a particular moment in the past. If we were to choose a snapshot to represent the natural state of things, which moment would we choose?
About 60 million years ago, the mid-Atlantic ridge between continental plates began to form. This would lead to the eventual rising of Iceland from the sea, starting about 16 million years ago. Iceland’s restructuring by volcanic activity continues today, as evacuations across the Reykjanes peninsula about a week after I talked with the tour guide there shows.
At the same time that the mid-Atlantic ridge was starting to form, the ancestors of today’s lupins were starting to grow root nodules, the structures that allow their descendants to so efficiently house nitrogen-fixing bacteria. Or perhaps I should say that bacteria were evolving ways of coaxing root nodules out of legumes: the genes needed for root nodule development in legumes are regulated by signaling molecules secreted by bacteria. In a real sense, the root nodules are disruptive changes to the native structure of plant roots made by bacteria that will make the plants their home. The nodules that result on lupin roots house entire ecosystems of nitrogen-fixing bacteria, with hundreds of different species capable of rebuilding the plant roots to their own ends.5
Of the bacteria that colonize the lupin roots, which are the invasive, alien ones? At what point on this timeline of evolution does it cease to be natural?
The Little Prince comes to realize how much he loves his rose through his interaction with a fox:
“Come and play with me,” the little prince proposed. “I’m feeling so sad.”
“I can’t play with you,” the fox said. “I’m not tamed.”
…
“What does tamed mean?”
“It’s something that’s been too often neglected. It means, ‘to create ties.’…For me, you’re only a little boy just like a hundred thousand other little boys. And I have no need of you. Any you have no need of me, either. For you I’m only a fox like a hundred thousand other foxes. But if you tame me, we’ll need each other.”
“Tame” is typically used in opposition to “natural”. A natural animal is a wild one, and one who has been molded by human action is tame. But using the definition the fox gives the Little Prince all of creation is tame, connected intimately to everything else.
The lupin roots are commandeered by bacteria, which fertilize the soil in which the pines grow. The foxes stalk birds in the foliage, a task made more difficult by the dimensions of the newer pines. Humans alone pretend to stand outside the system, needing nothing. We imagine that our actions can either corrupt or restore it, but insist that we are separate, and in control.
Is the lupin invasive because humans introduced her to Iceland, or because we cannot control her? Is she a good plant or a bad plant? Is she wild or tame? And which are we?
I am indebted to
at for his writing on “invasive” and “immigrant” species in informing my thinking on Iceland’s introduced species.For instance, see Vikings razed the forests. Can Iceland regrow them? by Henry Fountain, New York Times, 2017.
I was very fortunate to be able to travel to Iceland and Norway recently.
Anna Kuprian in Negotiating contested landscapes: The lupin controversy in Iceland (2016) does a nice job of summarizing cultural reasons for condemning the lupin as an “alien invasive species.”
How Iceland helped humans reach the moon, BBC News, 2019.
Msaddak et al. (2023) “Lupin, a Unique Legume That Is Nodulated by Multiple Microsymbionts: The Role of Horizontal Gene Transfer,” International Journal of Molecular Science 24(7): 6496. doi: 10.3390/ijms24076496
The group Mossy Earth is doing reforestation in Iceland and I believe one of their YouTube videos mentions that lupine pollen has been found in Icelandic soil layers corresponding with times before the last Ice Age. Perhaps once long ago it was "native."
Excellent article, Doctrix Periwinkle !
! If I were Icelandic, I’d celebrate the presence of Alaskan lupines.