14 June 2026
The Lupine Invasion of Iceland
It seemed like a good idea at the time… In 1945, the Icelandic Forest Service took seeds of the Nootka Lupine (Lupinus nootkatensis) from its Alaskan home and introduced it to the island’s most eroded areas in the hope it would help to replenish the soil. Seen as a bridging tool to hold back erosion until trees could be re-established, the lupine had other ideas. It quickly spread, and is now classified by Iceland’s environment agency as an invasive species. Soon, it could cover up to ten percent of the country. On the upside, it is very, very pretty. Image Credit
This story began over a thousand years ago. Iceland was first permanently settled in 874 AD and for many centuries, life was hard for its inhabitants. Dense birchwood forest covered about a quarter of the island – and being stuck on the North-Atlantic Ridge, the settlers did the obvious thing – they cut the forest down. It was cleared to graze sheep, to build houses, to warm the growing population through. After three centuries of human activity, the island was bare, the forest cover effectively gone except in a few isolated places. 95% of its forests had vanished. Perhaps the settlers can be forgiven for their lack of foresight – how were they to know that Iceland’s soil takes longer to form but erodes much more quickly than European soil?
After the forests were cleared, erosion took hold - an irony
written into the landscape itself. Without
tree roots to keep it in place, the island’s soil began to move and when the
winds blew in, huge dust storms removed the destabilised andosol (fertile soils
formed in volcanic tephra and ash) that the forest had spent thousands of years
forming. Into the sea it went. These
dust storms were not mild, either – they could go on for weeks. This issue led to the first reforestation
projects, starting in 1882. However,
this led to little success. At the start
of the 20th century, Iceland had 1% forest coverage. It has approximately 2% today. It wasn’t happening quickly enough so the
search for a new solution began – one which would culminate in the introduction of
the nootka lupine.
The mistake that the tree planters made was, in hindsight,
an obvious one. Plant more trees, get
more trees, right? Unfortunately, the soil has changed since the settlers
cleared the forests – the top layer was gone. The andosol was gone and what
remained wasn’t much good for growing trees in. What was needed was something that would stop
the soil being eroded, fix nitrogen into the soil on a huge scale and build up
its overall chemistry.
The nootka lupine ticks all those boxes. The idea was that if you plough under the lupines,
the nitrogen they have collected goes back into the soil. Revegetation of Icelandic flora would quickly follow. But how was it, of all plants, selected for
the job?
At the end of the Second World War a committee was set up
and a representative dispatched to Alaska to research and collect plants that
might fare well in the Icelandic environment. Hákon Bjarnason (the
representative and the country’s chief forester) returned with a suitcase full
of seeds, including lupins. The summer of 1946 would see the first blue spikes
on the Icelandic landscape.
Up to the 1970s, the lupines kept to areas close to the capital Reykjavík. Then, after this initial success, seeds were collected and planted elsewhere. Packets of seeds were made available at gas stations so people could choose to plant them wherever they wished. And they did. The spread became haphazard and uncontrolled, made worse by the lupine’s own natural fecundity.
After 1976, the lupines diffused across the island very,
very quickly – they went on something of a rampage. An American invader was about to conquer a Viking
land. Now, this could look at first sight as a win-win situation – extremely
low cost and the hope of enriched soil coming true as each year the spread of
purple flowers became more evident across the country. However, its spread has been so fast (tempted
to say “and so furious”) that it now grows in areas where it directly competes
with native plants and grasses. And guess what’s currently winning?
Some argue that the lupins will naturally fall back as trees
grow and shade increases – and there is some limited evidence for this. Yet,
determined to stop the purple invader from marching into the barren heart of
Iceland, conservationists have established new lines of defence across the
central highlands. The irony is that the plant has become one of Iceland's most
photographed attractions. Drawn by vast swathes of violet stretching across the
landscape, some tourists have even begun timing their visits for June and July,
when the lupins are at their most spectacular. And many Icelanders - who call it lúpína - love this
new(ish) addition to their landscape, too.
So, while the lupine continues its advance, an equally
persistent conflict rages among humans. The plant has become the focus of a
deeply divided debate about invasive species and ecological intervention.
Decades of scientific research have shed light on the problem, but not settled
the argument. What does the future hold
for the lupins of Iceland? Only time will tell.
