Spring Returns to the Lava Plateau: The Quiet Revival of Mt. Fuji’s Mosses and Lichens
When spring arrives at the foot of Mt. Fuji, the first to notice are neither people nor animals.
It is the mosses and lichens that blanket the surface of the lava plateau.
In March, as snowmelt begins to seep into the cracks of the ancient rock, the world still looks brown and lifeless to human eyes — yet a quiet revival is already underway on the surface of the lava.
The Lava Plateau: An Extreme Environment
The lava plateau spreading across the foothills of Mt. Fuji looks, at first glance, far too harsh for any living thing to call home.
Formed from lava that cooled and hardened about 1,000 years ago, this land has almost no soil. It retains almost no water, bakes in summer heat, freezes below zero in winter, and offers almost no nutrients.
And yet, it was mosses and lichens that first took root here, building the foundation of an entire ecosystem. Over hundreds of years, they have slowly broken down rock, accumulated organic matter, and paved the way toward true soil.
Lichens in particular are remarkable organisms — a symbiosis of fungi and algae — capable of breaking down bare rock itself as they grow. They are the unsung pioneers that have been slowly turning Mt. Fuji’s lava fields green.
Where Do They Go in Winter?
Both mosses and lichens enter a state called desiccation dormancy during winter.
They reduce their metabolism to nearly zero and simply wait for spring. They may look dead — dried and brown — but they are not. You may have seen a dry brown patch of moss spring back to vivid green almost instantly when water is added. That remarkable regenerative power is the secret behind their winter survival.
As a guide walking the foothills of Mt. Fuji, I begin to notice something in late February to March: the surface of the lava starts to take on a subtle wet green hue. It is the signal that snowmelt has begun to moisten the moss. This barely visible shift in color is the very first sign that spring has arrived.
Mosses and Lichens to Look for in March
Hinoki Moss (Pyrrhobryum dozyanum)
One of the larger mosses commonly found on the lava around Mt. Fuji. Its leaves are densely arranged like cedar needles, giving it a strong, striking presence. In early spring, new shoots emerge in a vivid yellow-green that catches the eye.
Hair Cap Moss (Polytrichum spp.)
The classic image of what moss “should” look like — upright stems with spreading leaves. In spring, the sporophytes begin to grow: slender stalks topped with small rounded capsules, like a miniature forest. Beautiful and unmistakable.
Plated Lichen (Parmotrema tinctorum)
A leafy lichen that clings to tree bark and rock surfaces. Recognizable by its gray-green frilled edges, this species is highly sensitive to air pollution — its presence is proof of clean air. It is a symbol of the pure atmosphere of Mt. Fuji’s foothills.
Old Man’s Beard (Usnea spp.)
A string-like lichen that hangs from tree branches like a beard. Also known as “forest whiskers,” it is commonly seen in the dim interior of the Aokigahara forest. It keeps its form through winter and sends out new growth as spring returns.
What Mosses Can Tell Us
Mosses and lichens act as mirrors of their environment.
A rich variety of species indicates high humidity. The presence of Parmotrema tinctorum signals clean air. The distribution of mosses across the lava plateau reflects subtle changes in water flow and sunlight with remarkable precision.
When I guide visitors through the forest, paying attention to the mosses underfoot gives me a sense of the history of a place. A thick accumulation of moss means moisture has been sustained there over a long period of time. A sparse, thin covering means the lava is still young — the process of becoming soil has barely begun.
Tips for Walking the Mt. Fuji Foothills in Spring
- Watch your step: Moss can take decades to recover if trampled. Always stay on the trail.
- After rain is best: Moss is most beautiful when wet. A walk the day after rain is highly recommended.
- Bring a hand lens: The sporophytes of mosses and the fine structures of lichens reveal a whole other world under magnification. We recommend the Bausch & Lomb 10x Coddington Magnifier — the same type used by professional naturalists in the field.
- Use morning light: Low-angle morning light brings out the three-dimensional texture of moss — ideal for photography.
Recommended Gear for Your Mt. Fuji Nature Walk
Walking the lava plateau is easier and safer with the right equipment. Here are two essentials we recommend:
- 🔍 Bausch & Lomb 10x Coddington Magnifier — Perfect for observing moss sporophytes and lichen structures up close. A must-have for any nature enthusiast.
- 🥾Black Diamond Trail Trekking Poles－Lightweight and adjustable, ideal for uneven lava terrain. Helps protect your knees on rocky ground.
Experience the Lava Plateau for Yourself
The best way to discover the hidden world of Mt. Fuji’s mosses and lichens is to walk the lava plateau with a knowledgeable local guide.
- 🌿 Book a Mt. Fuji nature walk tour – Viator ※Viatorリンクに差し替え
- 🌲 Aokigahara Forest guided tours – Viator ※Viatorリンクに差し替え
Closing Thoughts
Spring tends to draw our eyes to cherry blossoms and fresh green leaves. But at the foot of Mt. Fuji, an even quieter revival begins long before any of that — in the world of the very small.
Get down on your knees on the lava and look five centimeters ahead. There you will find the silent, powerful spring of the pioneers who have been cultivating this land for hundreds of years.
