The Forest Unseen: A Year’s Watch in Nature, David George Haskell

March/April 2026

* The Forest Unseen: A Year’s Watch in Nature, David George Haskell, 2012

In this book a biologist marks out a one-square-meter patch of forest, and visits it over fifty times during the course of a year. On each visit he observes and reflects on what he sees, starting with the concrete and then exploring a web of connections and associations that illustrate the systemic and interconnected aspects of the ecosystem. One part ecology, one part biology, one part poetry. Having read the first few entries it looks like it will be a great read. It was a finalist for the Pulitzer Prize.

Preface

“I believe the forests ecological stories are all present in a mandala-sized area. Indeed, the truth of the forest may be more vividly and clearly revealed by contemplation of a small area than it could be by donning ten-league boots and covering a continent but uncovering little.

—The Forest Unseen, p xii

I sit next to the mandala on a flat slab of sandstone. My rules at the mandala are simple: visit often, watching a year circle past; be quiet, keep disturbance to a minimum; no killing, no removal of creatures, no digging in or crawling over the mandala. The occasional thoughtful touch is enough. I have no set schedule for visits, but I watch here many times each week. This book relates the events in the mandala as they happen.

—ibid., xvi

Phrases I like

• ankle-twistingly strewn with jumbled rock from the eroding bluff…
• the fat, wet smell of the woods
• muted leathery colors of decaying leaves
• supple physiology
• All the lichens’ hues are paint-stroke fresh
• winter-weighed lethargy
• snow has smoothed the forests fractured surface into a gentle swell and trough
• the whole flock is a rolling ball of agitation as it moves through the … forest
• The birds dance through the trees like sparks from a fire. They rest no more than a second on any surface, then shoot away.
• plumage, plumped, puffed
• light dances and flows through the moss, giving it an internal glow.
• a cloud condensed into animate matter
• the untidy mop of anthers at their center

January 1st—Partnerships [[Symbionts and parasites]]

• Lichens deal with the cold by shutting down. They give up their water; their physiology is so simple that they are not damaged by cold.
• Discussion of the lichen symbiosis of fungi and algae/cyanobacteria and how it works, and how successful lichens are (10% of the earth’s surface).

The lichens’ growth forms mountains in miniature, sandstone crags with variegated patches of moisture and sunlight. The highest ridges on the boulders are spattered with tough-skinned gray flakes. Dark canyons between rocks have a purple sheen. Turquoise glistens on vertical walls, and concentric circles of lime flow down gentle slopes. All the lichens’ hues are paint-stroke fresh. This vibrancy contrasts with the winter-weighed lethargy of the rest of the forest; even the mosses are muted and frost-bleached.

—ibid., 2

• The color of lichens are due to the color of their non-fungal symbiots, and by pigments the fungi secrete as sunscreens.
• More general discussion of symbiosis and endosymbiosis.
• Horsehair worms: They lay eggs in the stream, the larva hatch and are eaten by a snail or insect. If the host exits the stream and is eaten by a cricket, the larva consumes the cricket, and in its final act takes over its brain and causes it to enter the water, where the now mature worm bursts out of the cricket, and mates with other horsehair worms, producing eggs in the stream bed. The horsehair worm contrasts with the symbiosis of the lichen: it is an example of parasitism, where only the worm benefits.

All life melds plunder and solidarity. Parasitic brigands are nourished by cooperative mitochondria within. Algae suffuse emerald from ancient bacteria and surrender inside gray fungal walls. Even the chemical ground of life, DNA, is a maypole of color, a Gordian knot of relationships.

—ibid., 6

January 17th—Kepler’s Gift [[Snowflakes]]

• Discusses how water crystalizes into snowflakes — ties this to Kepler, who was curious about their six-sided symmetry and wrote a treatise on this, though he did not answer the question.
• He notes that snowflakes are unique in the square meter in that they provide a clear view of the effects of the geometry of atoms.

January 21st—The Experiment [[Chickadees]]

• Author takes off his clothes in sub-zero weather, and describes his body’s response. He contrasts this with a flock of Chickadees

The birds dance through the trees like sparks from a fire, careening through twigs. They rest no more than a second on any surface, then shoot away.

—ibid., 12

• Bergman’s rule: The size of a species increases in the northern part of its range. Often by about 10%
• Chickadees manage heat in several ways
  • They have a layer of downy feathers beneath their outer feathers that trap heat. As winter comes, they increase the number of feathers by 50%.
  • On cold days their muscles at the base of the feathers tense, and their feathered-covering becomes twice as thick.
  • Chickadee’s shiver to produce heat; this primarily involves the flight muscles in their chests, which accounts for about a quarter of their body-weight
  • Chickadees need 65,000 joules a day to stay alive in the winter, and about half of this is consumed by shivering. (A sunflower seed provides about a thousand joules.) Exceptionally acute vision (both in terms of color discrimination and resolution) aid them in hunting for food.

The chickadees’ acrobatic bodies let them put their vision to good use. A wing-flick takes a bird from one branch to another. Feet grasp a twig, then the bird falls, swinging from a branch tip. The beaks probe as the bird’s body pivots, still hanging, then wings flash open and the bird flits up to another small twig. No surface is left unexamined. The birds spend as much time upside down, peering under twigs, as they do upright.

—ibid., 17

• Chickadees also accumulate fat for the winter. But there is a tradeoff: fatter chickadees are more vulnerable to hawk predation.
• Chickadees also cache food in niches and under branches; because caches are vulnerable to looting, caching chickadees are more territorial
• Chickadees huddle in groups at night to preserve energy, and also their internal temperature drops by about 10 degrees, putting them into a hypothermic torpor.

January 30th—Winter Plants [[Heat Management]]

• How plants cope with cold: increasing intracellular sugar to lower freezing point; allowing extracellular water to freeze to generate heat of fusion; sequestering DNA and other organelles in the center of cells, and surrounding them with fats altered to remain fluid in the cold; allowing remaining intracellular water to leak out, desiccating the cell and providing further heating.
• Also, plants that remain green in the winter must deal with excess light to prevent chlorophyll-generated ROS from destroying cells. They do this by generating protective chemicals — vitamins — that absorb ROS/.

February 2nd—Footprints [[Winter grazing]]

• Deer are browsing the dormant plants in the mandela, chewing off the nutritious tips. Discusses the deer’s rumen, and how it uses anaerobic microbes to digest plant matter.
• Rumens, which evolved about 50 Ma, protect the microbes from oxygen, and provide a non-acidic environment because they are located before what is eaten reaches the stomach. The microbes in the rumen form their own ecosystem, with bacteria being preyed on by protists.
• Fauns start out with no microbial ecology, so it is not clear to me where the anaerobic microbes come from. ???
• The ecology of the rumen changes with the seasons, adapting to the kind of food being taken in: twig-ends in the winter, new leaves in the spring, etc. Doing something like putting out corn for deer in the fall can injur or kill them,
• A discussion of whether there are too many deer now — author argues that there are not, and what seems like too many is only because their numbers were artificially suppressed by hunting and habitat destruction/alteration, in the past.
• There is a final discussion of plants — like honeylocusts, holly trees, and osage orange — that evolved to in partnership with now-extinct mega-fauna. This is evident from the size of their seeds and/or how high up their thorns grow to protect them from over-browsing.

February 16th—Moss

• “Luminosity dominates this world: each leaf is one cell thick, so light dances and flows through the moss, giving it an internal glow.”
• Mosses are called “primitive,” but they are not. They are very different from the earliest plants. And, over time, they have grown more common, rather than being eclipsed by more ‘advanced’ plants.
• Plants evolved into four branches: first liverworts split off; then mosses; then hornworts, the closest relatives to ferns, flowers and their kin. [[What is the other branch??]]
• Mosses store and transport water on their surfaces, rather than internally.

The microworld of moss operates under different rules. The electrical attraction between water and plant cell surfaces is a powerful force over short distances, and moss bodies are sculpted to master this attraction, moving and storing water on their complex facades.

Grooves on the surface of stems wick water from the mosses’ wet interiors to their dry tips, like tissue paper dipped in a spill. The miniature stems are felted with water-hugging curls, and their leaves are studded with bumps that create a large surface area for clinging water. The leaves clasp the stem at just the right angle to hold a crescent of water. These trapped drops are interconnected by water trapped in woolly hairs and surface wrinkles. Moss bodies are swampy river deltas miniaturized and turned vertical. Water creeps from slough to lagoon to rivulet, wrapping its home in moisture. And when the rains stop, the moss has captured five to ten times as much water on its body as it contains within its cells. Moss carries a botanical camel’s hump as it trudges through long stretches of aridity.

—ibid., 37

• The inner concave surfaces of moss hold water; the outer concave surfaces capture sunlight and air.
• Moss copes easily with desiccation. They concentrate sugar in the cores of their cells to protect cellular machinery, and they keep a store of substances needed for cell repair on hand at all times. Their response to drought and flood is far more rapid than those of other plants, and that gives them a competitive advantage in certain areas and circumstances.
• Moss traps dust and absorbs heavy metals and other toxins. [[What becomes of them? Do they just sequester them, or do they chemically neutralize them by binding them into some less-mobile compound?]]

February 28th—Salamander

• He sees a small salamander of the genus Plethodon
• He describes the mating habits of this type of salamander, and notes that they demolish two myths: one that salamanders are dependent on water for breeding, and the second that only ‘higher’ animals care for their young — a fact belied by these salamanders
• Discusses how this salamander breaths through its skin, having discarded lungs to make its mouth more effective. And more on its natural history.

March 13th—Hepatica

• The first spring wildflowers, including Hepatica, are pushing up, causing the mat of dead leaves to buckle
• A nice description in stop motion of the breaching and blooming of the flower:

A Hepatica has finally pierced the litter, standing on a finger-high stem. A week ago, the bud was a thin claw, encased in silver fuzz. Slowly, the claw filled out, fattening and elongating as the air warmed. This morning, the bud’s stem is shaped like an elegant question mark, still covered in down, with the tightly closed flower suspended at the tip of the curve. The flower points demurely down, its sepals closed against nighttime raiders of pollen. […] The flower cracks open an hour after first light. The three sepals spread, revealing the edges of three more inside. The sepals are flushed with purple…

—ibid., 47

• The social history of the flower — how people understood and valued it — and the scholars who developed what became the doctrine of signs: the idea that the uses of a plant would be signified by its appearance.

March 13th-Snails

• “The largest snails travel alone, ply the crazily angled surfaces of the leaf litter, leaving the mossy hillsides for the nimble youngsters.”
• A very close-up view of the snail, through a hand lens.
• A discussion of what the snail sees, based on experiments, and speculation about whether a snail is aware of what it sees.
• This bit ends with the sun coming out, and a macro-view of how the snail disappears into a crevice.

Interlude & Comment

So far, in the book, there is a lot of close-looking,’ often beautifully depicted. It is nice to read a few sections, and then set the book aside. I find myself wishing for some larger view, some larger narrative about the forest as an ecosystem, although I’m not sure how that would fit into the focus-only-within-the-mandala approach.

Somewhere in the course of discussing these readings, we decided that we would try to sync our reading/discussions with the calendar. That will not be evident until we get to June…

March 25th—Spring Ephemerals

• This is the peak of sunlight on the forest floor: the sun is higher, but the forest canopy has not leafed out yet. Wildflowers are everywhere, and migrating birds are passing through. The plants that are flourishing right now are called Spring Ephemerals, and their lifestyle is adapted to take advantage of this point in time: many of them have underground bulbs, tubers or stems, which enables them to emerge rapidly to take advantage of the brief period of light; after the canopy leafs out, the will become quiescent.

The bright burning lives of the ephemerals ignite the rest of the forest. Their growing roots reinvigorate the dark life of the soil, absorbing and holding the nutrients that would otherwise be flushed out of the forest by the spring rains. Each root secretes a nutritious gel, creating a sheath of life around its hairy tip. Bacteria, fungi, and protists are a hundred times more abundant in this narrow halo, and these single-celled creatures provide food for nematodes, mites, and microscopic insects.

—ibid. 56

• Other plants, like the Toadstool Trillium, take a different path: they are adapted to the deep shade, and exert minimal energy to maintain themselves throughout the temperate season.
• There is a long discussion of bees of various sorts: generalists like bombyliid flies, which fertilize many types of flowers (but are not very effective at gathering pollen), and specialists that focus on a subset of flower types.

April 2nd—Chainsaw

The sound of a chainsaw provokes a mediation on our over-use of wood, and reflections on how we might do better.

April 2nd—Flowers

xxx

A fountain of anthers arches from the chickweed’s open bloom. A central dome, the ovary, is ringed by gracile, creamy filaments holding up tawny knots of pollen grains. These filaments soar away from the dome, holding the pollen away from the flower’s own pollen landing pads, the stigmas. The chickweed has three stigmas, planted at the peak of the ovary’s onion dome, each one waiting for a pollen-dusted bee to brush past.

The surface of the stigma is a forest of microscopic fingers, reaching out to embrace pollen grains. If the petals do their job and attract a bee, the stickiness of the stigma traps the rough-coated grains. Once pollen is caught, the stigma assesses it, rejecting any from different species. The plant also shuns its own pollen and that from close relatives, preventing self-fertilization and inbreeding.

—ibid., 68

• Discussion of how the architecture of a flower is influenced by its lifestyle: long-lived flowers can use structures to protect their pollen and nectar, making it available only to preferred pollinators; shorter-lived flowers make their pollen and nectar more available, but as a consequence may be robbed by ants or other thiefs who take pollen without performing pollination services.
• xxx

April 8th-Xylem

The weather is variable: one day may be warm and sunny; the next cold and sleety. Trees and other plants adapt differently to these conditions. The challenge is dehydration: opening stomata to support photosynthesis means that water is lost to evaporation. Furthermore, for trees, the price for getting their leaves high enough to intercept sunlight is the energy required to lift water from the forest floor to the canopy.

Water is lifted by depending on capillary action and its internal cohesiveness. One challenge that this brings is that cold weather can cause freezing, and that will interrupt the continuity of water columns in the xylem, forming bubbles. Maples deal with this problem by forming many xylem cells, and capping them; in a Maple, an embolism is not a big problem because there are many other paths for water. This approach gives Maple wood a porous appearance because of all the xylem cells. Maples also have sugary sap, which they can force up their xylem, and which can serve to clear out air bubbles so that old xylem can be reused. In contrast, Hickory trees spend the first part of each year re-growing their xylem. Their xylem cells are long and wide, and when they are functioning they are capable of transporting a huge amount of water; but these characteristics also leave the xylem prone to embolisms, so they must defer leaf-out until after all danger of a freeze is past.

April 14th-Moth

April 16th—Sunrise Birds

April 22nd—Walking Seeds

April 29th-Earthquake

May 7th—Wind

May 18th-Herbivory

May 25th-Ripples

June 2nd—Quest

Ticks! A short chapter on ticks, and how they live. Strains a bit to make an analogy between the quest for the grail, and the “questing” behavior of ticks after blood. But the chapter is pretty good, and really zooms in on ticks, describing their anatomy, and their “Hallers organs,” the means by which they sense CO2, sweat, heat, and vibration that signals the passing of their prey.

A tick takes time to find a spot on its host, ‘saw’ through the skin, and attach itself with a cement it secretes. The cement is stronger than the ticks muscles, and this is why the various means suggested to make ticks release their hold— like a hot match—are ineffective. As a tick takes in blood, it will retain blood cells while discharging filtered out water back into the bloodstream of its host—this is one of the reasons ticks are effective disease transmitters.

The main challenge ticks face is dehydration while they wait for a host to pass near by. One of their adaptations is that they secrete a saliva which can absorb water from the air, and which they then swallow for hydration.

…reading/discussion break …
[At this point, June 6) we have synced our reading with the calendar]

June 10th-Ferns

• Christmas Ferns stay green through the winter, taking advantage of the lack of canopy to carry on photosynthesis. (But I wonder how photosynthesis can be effective at cold temperatures?)
• The leaflets at the tips of the highest fronds of a Christmas fern are pinched and shrunken: they contain packets of spores that can be launched by catapult-like structures. To the naked eye the escaping spores look like puffs of smoke.
• A spore that lands in a propitious place grows into a small lillypad-like structure (a haploid gametophyte). This lives independently and eventually produces both eggs and sperm, which in turn will produce a new fern plant. This reproductive method works well in wet places, but in dryer conditions more modern plants fare better.
• A different fern—the rattlesnake fern—also launches spores, but they grow into underground tubers that depend on a fungus symbiotic for nourishment. But they, too, eventually produce eggs and sperm, and then the next generation. The adult rattlesnake fern continues its mutualistic relationship with the fungus—some never lift their fronds above the leaf litter.
• Flowering plants retained the lily pad structure, but keep it within the plant, where it will produced eggs and sperm. The frees flowering plants from the need for a moist environment to foster the growth of the lily pad.
• After flowering plants emerged, ferns continued to evolve — it is a mistake to think of ferns as primitive holdovers.

June zoth—A Tangle

July 2nd—Fungi

July 13th—Fireflies

July 27th-Sunfleck

August ist- Eft and Coyote

August 8th—Earthstar

August 26th-Katydid

September 21st—Medicine

September 23rd—Caterpillar

September 23rd—Vulture

September 26th-Migrants

October sth-Alarm Waves

October 14th—Samara

October 29th—Faces

November 5th- Light

November 15th—Sharp-shinned Hawk

November 21st—Twigs

December 3rd-Litter

December 6th—Underground Bestiary

December 26th—Treetops

December 3ıst—Watching

Epilogue

Acknowledgments

Bibliography

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