Kew Diploma student Matti Niissalo searches for lady's slipper orchids in Finland
Towards the end of a long day, as the sun’s rays were dwindling, I found myself strolling among hundreds of lady’s slipper orchids (Cypripedium calceolus). The last time I saw these lovely plants at this well-known site in Kallinkangas, near Keminmaa in north-western Finland, was seven years ago.
I nearly missed them this time, but amazingly, in this remote area, I bumped into an old friend who knows the location well and directed me to them. I was lucky – in these damp, boreal forests and fens he was the only person I saw in all the sites I visited during my trip.
As beautiful as lady’s slipper orchids are, they weren’t my reason for travelling all the way to Finnish Lapland. While working on a systematic botany project about Finnish species of the orchid genus Dactylorhiza, I realised how little studied these marsh and spotted orchids have been in northern Finland.
So I went to study them in their natural habitat and to collect samples, in the hope of shedding light on whether the wide range of common names actually relates to genetic variation.
Dactylorhiza is one of the largest orchid genera in Europe – even Finland is thought to have between four and eleven species. The northern fens where they grow are rich in biodiversity, quite unlike southern Finland, where agriculture and forestry have always been more intensive.
The sites I visited are mostly in western parts of Finnish Lapland – I started at Kemi, went up the ‘arm’ of Finland via Pallas-Yllästunturi National Park, and came back through Posio, an area in south-eastern Lapland.
Distinguishing different Dactylorhiza
Dactylorhiza is problematic to taxonomists, because many species look alike – most are highly variable and occasionally new species form through hybridisation and changes in chromosome numbers.
Recently, molecular studies have begun to help with identification. Scientists at Kew and elsewhere use genetic data to differentiate between species and find out about their evolution. With the aid of Lapland’s environmental officials, I managed to get permission to collect small samples of plants, which were dried in silica gel to preserve their DNA for later analysis at Kew.
I realised how unprepared for the trip I was as soon as I got out of the car at the first site and a thick cloud of insects enveloped me. As a Finn, I thought I knew all about the problem of mosquitoes – they are everywhere in Lapland, often accompanied by horse flies and midges. A net over the head keeps them off your face (though midges still manage to find a way through), and chemical repellents help to protect your hands if applied often enough.
But even with the strongest chemicals, you can never get rid of the dense cloud of insects that accompanies you everywhere. You have to stay covered up, which is uncomfortably hot in summer, but exposing any skin would be madness. I had been to Lapland several times before, but never in the height of the mosquito season at the beginning of July, nor in the low-lying wetlands where Dactylorhiza are found.
The good thing about working outdoors in Lapland in the summer is that the sun doesn’t set. It’s still light in the early hours of the morning, so you can continue working for as long as you have the energy. I started at seven in the morning and usually finished around midnight, when I parked the car next to a new site and crawled into the back to sleep.
To keep mosquitoes and midges out, I tried to avoid opening the car doors – sleeping in a tent was impossible. I couldn’t reach some of the sites I had permission to work in, as there wasn’t enough time to walk several miles into them.
Of the 16 sites I did visit, a few had no Dactylorhiza plants at all. In one area, the reason for this was clear, as there are now man-made ditches where the orchids used to be.
Some areas have remained intact and several of the wetlands I visited are as good, if not better, than the very best southern Finnish fens, at least when it comes to the numbers of orchids.
The highly variable narrow-leaved marsh orchid (Dactylorhiza traunsteineri), the early marsh orchid (D. incarnata) in its many forms, and the heath spotted orchid (D. maculata) grew alongside other orchids, of which coral root (Corallorhiza trifida), frog orchid (Coelo-glossum viride or Dactylorhiza viridis) and lesser twayblade (Listera cordata) were the most frequently found.
I also saw other treasures, such as the carnivorous plants Pinguicula alpina and P. villosa. Most of the sites aren’t visitor friendly. They consist of endless fen mixed with woodland, cut through by streams that are too small to appear on maps but too wide to jump across.
Being knee-deep in mud is unavoidable and you have to be careful if you’re working alone, as many of the sites are beyond mobile phone reception and tens of kilometres from the nearest habitation. But looking on the bright side, there’s little danger of meeting a bear, or even a reindeer, as they wisely avoid the most mosquito-infested areas.
The site in the highlands at Pallas-Yllästunturi National Park, which is the largest and most visited national park in Finland, was slightly more comfortable. It is located near the original collection site of Dactylorhiza psychrophila, which grows in the coldest regions of the Scandinavian mountains. D. psychrophila is probably related to, or even genetically inseparable from, D. fuchsii, the common spotted orchid, but it is much smaller. Hopefully, molecular studies will reveal something about the relationship of the two taxa.
In addition to the unanswered question of the relationship between D. psychrophila and D. fuchsii, my trip raised several other important queries. Does D. traunsteineri encompass another species in this area, namely D. lapponica? How genetically varied is D. incarnata in Finnish Lapland? And is there a clear difference between the closely related D. fuchsii and D. maculata?
DNA from Dactylorhiza
Back in the Jodrell Laboratory at Kew, work to extract DNA from the samples I collected has now finished. The next step is to sequence the material and analyse the data. With a little luck, this might answer some questions. It will probably raise new ones too, but this will all be good material for my next task – my Diploma dissertation.
Author: Matti Niissalo