Newsletter #198 ❄️ December — The Dark Month, Full of Life
Newsletter about nature and science
❄️ December — The Dark Month, Full of Life
🌘 A Month of Contrasts
December sits around the shortest day of the year, with the lowest number of sunshine hours. Even though solar radiation has increased in all months due to cleaner air and more high-pressure zones, December still feels like stepping into a dimly lit room.
But nature compensates.
We celebrate Christmas, the days start lengthening again, and—depending on November—there may still be mushrooms everywhere. Over 200 species are recorded in December, though that number will halve next month.
A few brave plants keep blooming too: a surprising white dead-nettle here, a lone dandelion there, and of course the indefatigable daisy, flowering the whole year round.
🌿 Plants in December
Besides the year-round bloomers, some species are at their seasonal limit—like yarrow and shepherd’s purse.
The forest looks bare, but a few species keep their leaves:
ivy
some ferns
brambles
And then there’s holly—the only tree still strikingly green. A female holly even carries bright red berries, our classic Christmas symbol of resilience and hope. In open spaces, holly can grow up to ten meters and reach 300 years of age.
Its tough, leathery, spiny leaves are iconic. A fun scientific mystery: older holly leaves lose their sharp teeth and become more rounded. Nobody knows exactly why.
Another evergreen of December is the mistletoe, a half-parasite living high in trees in southern Netherlands. Its berries are poisonous to humans, but birds spread the seeds by wiping their sticky beaks against branches—nature’s own glue trap.
Mistletoe is ancient folklore:
💚 symbol of peace
💚 protector against lightning
💚 sealing marriages
💚 and yes… still a license to kiss beneath it 😉
🍄 Mushrooms, Birds & Wildlife in December
December can be an excellent mushroom month—depending on the weather. Some species disappear quickly (birch boletes, chestnut boletes, yellow earthballs), but over 100 species still thrive this month.
Mushrooms on dead wood continue well into January:
elf cups
turkey tails
crust fungi
jelly fungi
tough tinder fungus
Birds fight through the cold. Hard frost (rare lately!) is tough on kingfishers and green woodpeckers.
Insects? Almost none above ground—but beneath the soil lies a bustling world. As Jac. P. Thijsse said: “There must be life down there, otherwise wrens and robins wouldn’t be so busy digging.”
Small mammals stay hidden.
Hedgehogs hibernate, squirrels stay close to their food stores, and hares and rabbits rely more on twigs and roots in December. After steep declines (up to 75%), both populations are slowly stabilizing.
Large mammals? Thriving.
Encounters with roe deer and wild boar are more common than ever—sometimes too common. Roe deer now number over 220,000 in the Netherlands. Wild boar officially belong only on the Veluwe and in North-Limburg, but they wander freely. Their population doubled from 4,800 in 2019 to over 10,000 in 2025, and road accidents are daily occurrences.
🔎 December Tips for Your Walks
🌼 Look for winter bloomers — far more species flower than you’d expect.
🍄 Hunt mushrooms on dead wood — discover jelly and tinder fungi.
🌳 Spot holly trees — berry-bearing trees show you the male/female ratio.
🦢 Enjoy the goose season — greylag, brent, barnacle, bean, and Canada geese.
🐦 Observe garden battles — who wins: the blue tit or the great tit?
🎙️ Listen to the full Dutch episode on mennoenerwin.nl — your monthly guide to nature, science, and wonder.
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