This Is Not Ordinary Snow – what you see here is Crown Snow-Load

Even if you live in a warm country, you’ve likely seen snowfall at least in movies or documentaries. During snowfall, snow drifts from the sky to the ground, and if it’s cold enough, it begins to accumulate into an increasingly thick layer on the ground and, for example, on tree branches. But there is something even more magical – a thick and heavy snow-load that seems to gather invisibly, transforming trees into magnificent white giants. This is not created by ordinary snowfall but by the formation of crown snow-load.

Artcile by @jonna_saari

Finland’s Lapland is often advertised with winter images where trees are so thickly covered with snow that the tree itself is no longer visible; the snow has enveloped the tree from all sides. In such cases, the trees might resemble a giant white Michelin Man, Barbapapa, Moomintroll, or some other fairy-tale creature. These trees are covered with crown snow-load. Even a Moomin mug has been designed and named after this beautiful natural phenomenon!

Crown snow-load, or “tykky” in Finnish, requires specific conditions to form. In Finland, the southernmost place where crown snow-load can develop is Koli National Park in Lieksa, Eastern Finland. So even if you see trees under a thick layer of snow after heavy snowfall in, say, Helsinki, it is not crown snow-load. This is something that even Finns might get confused about. Not everyone is familiar with the phenomenon of crown snow-load formation, and in Southern Finland, you might hear people talking about crown snow-load (tykky, tykkylumi) when, in reality, it’s just an ordinary thick layer of snow on trees.

North of Koli and especially in Lapland, crown snow-load is common in winters until the spring sun warms enough to strip the trees bare of crown snow-load together with the wind. Sometimes, even in the middle of winter, Lapland can experience such mild and windy weather that it strips the landscape of its crown snow-load. If this hasn’t happened, the best time to admire crown snow-load is in January and February, when pastel hues still paint the northern sky with beautiful colors. At the same time, the days begin to lengthen, allowing you to enjoy nature a little longer each day before darkness falls.

Crown snow-load begins to form, for example, when the air is humid—such as in foggy conditions—and then it starts to freeze. The moisture in the air begins to accumulate as frost on surfaces like tree branches, and the layer keeps growing. For the crown snow-load layer to grow, this process must repeat itself multiple times, and there must be no warm periods in between.

The lacy ice crystals resemble magnificent winter frost flowers and are truly beautiful to behold. This also explains why crown snow-load is not only on top surfaces but also coats the sides and undersides. In the right conditions, just the right kind of wind can accelerate the formation of crown snow-load, as it carries particles onto the surfaces of branches. However, too strong a wind can strip trees of crown snow-load. For trees, crown snow-load is a heavy burden to bear, and it can easily break or even topple them. This is, of course, entirely natural, and a fallen, decaying tree continues to play an important role in enriching the northern ecosystem even after its life has ended.

Another way crown snow-load can form is when wet snow starts to accumulate and freeze onto surfaces like tree branches. This moist accumulation also binds ordinary snowflakes to itself.

Trees covered in crown snow-load are incredibly beautiful and striking in appearance. They stand like white giants in a landscape that is usually already quite impressive. However, it’s important to know that it’s wise to keep a small safety distance from trees laden with crown snow-load. The snow-load can detach and fall onto a person, and because it weighs an enormous amount and it’s not easy to move quickly in deep snow, the situation can be extremely dangerous. It’s crucial to be aware of this risk and to admire crown snow-load trees preferably from a slight distance rather than right at their base—or even touching them.

*Here, the temperature rising above freezing (C) and strong winds have stripped the fell’s trees of their thick crown snow-load just the night before. Luckily, I wasn’t there at that exact moment!*

My Tips for Admiring Crown Snow-Load:

Choose the right time for your trip: Plan your visit for December, January, or February. In December and January, you can also experience the polar night in Northern Lapland, and the farther north you go, the better your chances of spotting the Northern Lights in the evenings.
Travel far enough north: At least to Koli! In Lapland, I recommend destinations such as Levi, Ylläs, Pyhä, Luosto, and Saariselkä. In these locations, you can admire crown snow-load even from the roadside, without needing to venture into the wilderness. These little towns also offer amenities like accommodations and restaurants and are accessible by public transport.
Join a guided snowshoeing tour: Guided tours are available for example in Koli, where you’ll also find a marked and safe snowshoeing trail. You can also rent snowshoes and other winter gear for a self-guided excursion. Snowshoeing in untouched snow can be very strenuous, but on a marked trail, it’s enjoyable and relatively easy. You don’t need to worry about getting lost and can focus on enjoying the scenery.
Be cautious near trees covered in crown snow-load: Keep in mind that under certain conditions, the heavy snow-load can fall, which could be dangerous. Always approach with care.
Always respect nature: Behave responsibly and never ever litter. Leave no trace of your visit except for footprints in the snow.