107 Fun Facts About Trees and Forests

Which tissue carries the sugars made in a tree's leaves to the rest of the plant?

In trees the phloem is the innermost layer of the bark, which is why stripping a ring of bark around a trunk can starve the roots and kill the tree.

Which term describes trees that shed all their leaves for part of every year?

Deciduous trees drop their leaves to get through winter or a dry season: bare branches lose far less water and are much less likely to snap under a coating of ice.

What is the name of the world's tallest known living tree?

Hyperion, found by two naturalists in 2006, stands about 380 feet (116 m); in 2022 the park closed the ground around it, on pain of a fine or jail, because visitors were trampling its base.

Which biome has long cold winters, short mild summers and is dominated by conifers like spruce and pine?

Boreal forest, or taiga, suits its trees for a reason: their narrow, tapering shape and drooping limbs shed heavy snow, and needles kept through winter can go to work as soon as the light returns.

What part of a tree is responsible for absorbing water and nutrients from the soil?

A tree's roots anchor it to the ground and are crucial for absorbing the water and dissolved mineral nutrients that the tree needs to grow.

Which tree product replaced cotton and linen rags as the main raw material for paper?

Wood pulp answered a rag shortage: in the 1840s Charles Fenerty in Nova Scotia and Friedrich Keller in Europe each worked out how to grind wood into paper, though mills took decades to switch over.

Which term means restocking trees where forest has been cut or destroyed, as opposed to planting where none grew before?

Reforestation can happen on its own as well as by deliberate planting: it is the natural or intentional restocking of forests and woodlands depleted, usually, by deforestation.

Which tree has fan-shaped leaves that turn golden yellow in autumn?

Ginkgo biloba is the last survivor of a plant group over 200 million years old, and a tough one: ginkgos scorched by the Hiroshima bomb in 1945 budded again and still grow.

The Amazon Rainforest is primarily located on which continent?

The vast majority of the Amazon Rainforest, the world's largest tropical rainforest, is located within the borders of South American countries, primarily Brazil.

Methuselah, one of the world's oldest known individual non-clonal trees, belongs to which species?

Bristlecone pine Methuselah has stood in California's White Mountains for more than 4,600 years; an even older one, Prometheus, was felled for research in 1964 with the Forest Service's permission.

Which gas do trees absorb from the atmosphere for photosynthesis?

Carbon dioxide, not soil, supplies a tree's bulk: wood is about half carbon by weight, and when Jan van Helmont grew a willow for five years it gained 74 kg while its soil lost just 57 grams.

Which tree is known for white bark that peels away in thin, papery sheets?

Birch bark is waterproof as well as light, which is why peoples across northern North America stitched sheets of it into canoes, bowls and wigwam covers.

Which Norway spruce on a Swedish mountain has kept resprouting from the same roots for about 9,500 years?

Old Tjikko's visible trunk is only a few centuries old: the spruce keeps sending up new stems from roots carbon-dated to about 9,550 years, and it was named after its discoverer's late dog.

Which country contains about 60% of the Amazon rainforest?

Brazil holds about 60% of the Amazon and Peru about 13%; a corner of the forest even lies in France, by way of its overseas department of French Guiana.

What is the scientific study of tree rings, used to date past climates and events, called?

Dendrochronology was founded by an astronomer, A. E. Douglass, who went looking for sunspot cycles in tree rings and ended up dating the Southwest's ancient pueblo ruins from their roof beams.

Through what process do trees release water vapor into the atmosphere, contributing to the water cycle?

Transpiration does two jobs: water evaporating from the leaves is the pull that lifts more up the trunk, and one large tree can give off 40,000 gallons (151,000 litres) in a year.

Which term describes a forest left for centuries without major disturbance such as logging?

Old-growth forest is marked as much by death as by age: standing dead trunks and fallen logs are part of what defines it, and species such as the northern spotted owl depend on that structure.

Which tree's dark, dense heartwood is prized for fine furniture and musical instruments?

Ebony is a dense black hardwood, most commonly yielded by trees in the genus Diospyros, prized for its ornamental value and use in fine woodworking.

Which compound makes up 40 to 50 percent of wood and about 90 percent of cotton fibre?

Cellulose is the fibre that stiffens a plant's walls, yet almost no animal can digest it unaided: termites and cattle rely on microbes in their guts to break it down.

What can the annual growth rings inside a tree trunk tell scientists about?

Tree rings, or annual growth rings, provide a chronological record of a tree's life, revealing its age and reflecting environmental conditions like rainfall and temperature in specific years.

Which conifer was unknown to science until bushwalkers found a grove of it in a remote Australian canyon in 1994?

Wollemi pine survives in the wild only as a few stands at a secret site; when bushfires closed in during 2019-20, firefighters were winched in by helicopter to set up an irrigation system and saved them.

Silkworms are raised almost entirely on the leaves of which tree?

Mulberry trees went into English gardens after James I urged landowners in the early 1600s to raise silkworms; the home-grown silk he hoped for never took off, but a few of those trees still stand.

Which four-season biome of the mid-latitudes is dominated by broadleaf trees rather than conifers?

Temperate deciduous forest grows on some of the most fertile soil of any biome, which is why so much of the original forest in Europe, China and eastern North America was cleared for farmland.

Plantations of which crop have replaced large areas of rainforest in Indonesia and Malaysia?

Oil palm gives far more oil per hectare than any rival crop, which is why it spread so fast: Indonesia and Malaysia now dominate a trade that supplies over a third of the world's vegetable oil.

Many lodgepole and jack pines keep their seeds locked away for years and release them mainly after which event?

A wildfire melts the resin sealing the seeds in, so they fall on freshly cleared ground just as the competition has burned away, and the pines come back in dense stands.

What is the scientific study of trees and other woody plants called?

Dendrology takes in shrubs and woody vines as well as trees, which is just as well, since botanists have no agreed definition of exactly what counts as a tree.

Which forest layer is formed by the interlocking crowns of mature trees and catches most of the sunlight?

Canopy leaves take so much of the light that only a few percent reaches the floor of a tropical rainforest, which is why the ground beneath is often surprisingly bare.

Which organisms link tree roots underground in networks nicknamed the 'wood wide web'?

Fungi called mycorrhizae wrap around or grow into a tree's root tips and reach soil the roots cannot; the tree pays for the water and minerals they bring with a sizeable share of its sugars.

What term describes trees that retain their leaves or needles throughout the year?

Evergreen does not mean everlasting: the trees shed old leaves a few at a time rather than all at once, and a single pine needle may last anywhere from 18 months to 40 years.

Which trees grow with their roots in salt water along tropical coasts, propped up on tangled stilts?

Mangroves keep most of the salt out at the root, and the tangle that props them up also slows waves and storm surges, so the shore behind a mangrove belt erodes far less.

What is the green pigment in leaves that absorbs sunlight for photosynthesis?

Chlorophyll looks green because green is the light it uses least: it soaks up red and blue to power the leaf and bounces most of the green back to your eye.

Roughly what share of the world's tree species are found in South America, the continent with the most?

About 43%: of roughly 64,100 known tree species, South America holds the largest share, ahead of Eurasia at 22% and Africa at 16%.

Pando, a Utah organism of roughly 47,000 identical stems, is a clone of which species?

Quaking aspen spreads by sending up new trunks from its roots, so all of Pando's stems are one male plant weighing about 6,000 tonnes, generally held to be the heaviest organism known.

Which giant sequoia in California's Sequoia National Park is the largest living tree by volume?

General Sherman is neither the tallest tree nor the widest; it wins on bulk because its trunk barely tapers, staying over five metres thick some 18 metres above the ground.

Natural rubber is made from which milky fluid, tapped from cuts in a tree's bark?

Latex made fortunes in the Amazon until Asian plantations undercut it; they grew from some 70,000 rubber-tree seeds that Henry Wickham shipped to London's Kew Gardens in the 1870s.

How does extensive forest cover help guard against natural disasters?

Root systems bind soil in place, so clearing forests is one of the leading human causes of erosion, flooding and landslides. China banned logging in 1998 for exactly this reason.

Which conifer is unusual in dropping all its needles every autumn?

Larch is one of the few conifers to stand bare all winter, yet no tree is hardier: larches grow farther north than any other, right to the edge of the Siberian tundra.

What is it called when trees naturally shed branches in response to stress or shading?

Self-pruning sheds branches that cost more than they earn in the shade; foresters exploit it by planting trees close together, so the lower limbs drop early and the trunks yield knot-free timber.

Oaks and sweet chestnuts belong to a plant family named after which other tree?

Beech, Fagus in Latin, gives the family Fagaceae its name, and its members carry their nuts in a cup or spiny husk; the horse chestnut, despite the name, belongs to a different family altogether.

Which forest layer is made of shrubs and saplings growing above the ground but below the crowns of the big trees?

Understory plants live beneath the canopy without ever pushing through it to any great extent; the layer is also called underbrush or undergrowth.

Which pigments, present in leaves all summer but masked by green, give autumn foliage its yellow?

Carotenoids are in the leaf all along and only show once its green pigment breaks down; the reds are a different story, coming from anthocyanins that the leaf makes fresh as autumn sets in.

Which of these trees is a traditional Christmas tree choice?

Various species of pine, fir, and spruce trees, all conifers with evergreen needles, are widely used as Christmas trees and are central to many holiday traditions.

What is the term for the layer of dead leaves, twigs, and other organic matter on the forest floor?

Litter is how a forest feeds itself: as decomposers break the fallen leaves down, the nutrients return to the soil for the trees to take up again, quickly in the tropics and far more slowly in the cold north.

Which two countries contain the largest areas of taiga?

Russia and Canada hold the largest sweeps of taiga; its cold, boggy ground rots dead plants so slowly that vast stores of carbon have built up there, much of it as peat.

What are the specialized cells that carry water and minerals from a tree's roots upward called?

Xylem does its work dead: the cells hollow out into pipes as they mature, and the xylem laid down in earlier years is the wood that makes up the trunk.

Which extremely fast-growing tree is often used for paper production and as an ornamental?

Poplar grows fast enough to be cropped every few years, and its wood has a grander past: Italian Renaissance painters worked on poplar panels, the Mona Lisa among them.

What is the scientific management of forests for timber and conservation called?

Silviculture is where historians trace the idea of sustainability: in 1713 Hans Carl von Carlowitz, facing timber shortages that were crippling Saxony's mines, argued for cutting only as much wood as could be regrown.

A strobilus is the botanical term for which part of a conifer?

A cone on a pine is really two things: the woody ones that hold the seeds are female, while the male cones are small, soft and short-lived, dropping off once they have shed their pollen.

What process do trees use to convert sunlight into energy?

Photosynthesis is the process by which green plants, including trees, use sunlight, water, and carbon dioxide to create glucose (sugar) for food and release oxygen as a byproduct.

The bark of which tree was the original source of the malaria drug quinine?

Cinchona bark was Europe's malaria remedy from the 1630s; its bitter quinine, mixed with sugar and soda by the British in India to make it drinkable, is how tonic water was born.

Which tree's wood was the traditional material for the English longbow?

Yew staves pair sapwood that stretches on the bow's back with heartwood that resists compression on its belly; demand so depleted Europe's yews that a 1472 law made every ship docking in England bring bowstaves.

Acorns are the nuts of which tree?

Oak woods owe a lot to forgetful hoarders: jays and squirrels bury acorns by the thousand for winter, and the ones they never come back for sprout into new trees.

Sherwood Forest, of Robin Hood legend, lies in which English county?

Nottinghamshire's Sherwood was a forest in the medieval sense, a royal hunting preserve under its own laws rather than solid woodland: much of it was open heath, and it once covered about a quarter of the county.

Which species includes the tallest living trees on Earth, reaching over 115 metres?

Coast redwood hugs a foggy strip of the California and Oregon coast for good reason: in the rainless summers it drinks fog through its leaves and bark, and fog drip supplies a large share of its water.

Which tree appears on the national flag of Lebanon?

Cedar of Lebanon was felled for millennia, by Phoenician shipbuilders and, in the biblical account, for Solomon's temple; so little survived that the remaining groves are now strictly protected.

Which country produces about half of the world's cork, stripped from the bark of its cork oaks?

Portugal's cork oaks are first stripped at about 25 years old and then every nine to twelve years; the bark grows back each time, so one tree can go on yielding cork for well over a century.

Bacteria in the root nodules of alders supply the tree with which nutrient?

Nitrogen fixed by Frankia bacteria in the nodules feeds the alder, and its fallen leaves then enrich the ground, which is how alders turn raw glacial gravel into soil that other trees can use.

Which great ape's name comes from Malay words meaning 'person of the forest'?

Orangutan joins the Malay words orang, 'person', and hutan, 'forest'. The name fits: the apes spend most of their time in trees and build a fresh sleeping nest of branches each night.

Which giant brown seaweed forms towering underwater forests along cool coastlines around the world?

Kelp can grow as much as 30 to 60 cm in a single day in ideal conditions. Its forests shelter seals, sea lions and sea otters, which keep kelp-eating sea urchins in check.

Bamboo can tower like a forest of trees, but botanically it belongs to which plant family?

Grasses include every bamboo, and the giant species are the family's largest members, with stalks up to 46 meters long. Bamboos are also among the fastest-growing plants in the world.

Which golden gemstone, sometimes found with ancient insects trapped inside, is fossilized tree resin?

Amber starts out as soft, sticky resin oozing from a tree, which is why it sometimes holds insects and plant fragments, known as inclusions.

Which Himalayan country's constitution requires 60 percent of its land to stay forested for all time?

Bhutan wrote the promise into the constitution it enacted in 2008. Forest covered about 71 percent of the country in 2020, comfortably above the legal minimum.

The Tree of Ténéré, once called the most isolated tree on Earth until a truck hit it, stood in which desert?

Sahara caravans used the lone acacia as a landmark until a truck driver knocked it down in 1973, when it was about 300 years old. A simple metal sculpture now marks the spot in Niger.

Which popular spice is the dried inner bark of a tree, with the 'true' variety originating in Sri Lanka?

Cinnamon bark is pried off the cut stems in long rolls that curl into tubes as they dry. Most of the spice sold internationally is really cassia, from related species.

Ashdown Forest in East Sussex was the real-life setting that inspired which series of children's stories?

Winnie-the-Pooh author A. A. Milne had a country home beside the forest, which became the Hundred Acre Wood. Illustrator E. H. Shepard drew its real landscapes for the books.

Forest bathing, the practice of unwinding by soaking up the atmosphere of the woods, began in which country?

Japan gave the practice its name, shinrin-yoku, in 1982, when the head of its forestry agency coined the term. No water is involved: bathers simply take in the forest through their senses.

The bark of which riverside tree gave chemists salicin, the compound that led to aspirin?

Willow gave salicin its name, from Salix, the tree's genus. A chemist first drew crystals of the compound from the bark in 1828, and work on its chemical relatives later led to aspirin.

Cuckoo clocks and a cherry-and-chocolate cake both come from the Black Forest, found in which country?

Germany holds the Black Forest in its southwest corner, close to the French and Swiss borders. In winter, many of its farmers made wooden cuckoo clocks to supplement their income.

The Daintree, home to some of the oldest surviving rainforest on Earth, grows on the coast of which country?

Australia holds the Daintree on its Queensland coast, north of Cairns. Its forests are put at well over 100 million years old, far older than the Amazon, so they have outlasted the dinosaurs.

Africa's largest rainforest, second in size only to the Amazon, fills the basin of which river?

Congo Basin rainforest is the only home of the okapi and the bonobo, and it also shelters African forest elephants and western lowland gorillas.

The Sundarbans, shared by India and Bangladesh, is the world's largest forest of which salt-tolerant tree?

Mangrove swamps in the Sundarbans spread across about 10,000 square kilometers of river delta and are known for their Bengal tigers, which live alongside crocodiles and chital deer.

The Monteverde Cloud Forest Reserve, famed for its orchids, is in which Central American country?

Costa Rica is where the misty mountain reserve was founded in 1972, and it holds more than 2,500 plant species. Its best-known native, the golden toad, vanished in 1989 and is now extinct.

Tongass, the largest national forest in the United States, covers most of the southeast of which state?

Alaska is home to all 16.7 million acres of the Tongass, an expanse larger than ten US states. Most of it is temperate rain forest draped over islands, fjords and glaciers.

Petrified Forest National Park, where ancient logs have turned to stone, lies in which US state?

Arizona groundwater once carried dissolved silica into the buried logs, where quartz crystals slowly replaced the wood. Traces of iron oxide gave the stone its rainbow of colors.

Which animal, the heaviest wild land mammal on its continent, roams Poland's Białowieża Forest?

European bison were hunted to extinction in the wild by 1927, and this forest lost its last free herd in the chaos around the First World War. Captive survivors were bred and returned here from 1929.

The Red Forest, named for trees that turned ginger-brown and died, surrounds the site of which nuclear disaster?

Chernobyl fallout killed the trees in 1986, and most were bulldozed and buried. With people gone, the young woodland that replaced them now shelters deer, moose, lynx and wolves.

Which 1908 explosion over Siberia flattened several million trees across more than 2,000 square kilometers?

The Tunguska event is blamed on a space rock that blew apart in mid-air, and no fragment of it has ever been formally identified. Whether it was an asteroid or a comet is still debated.

In which Shakespeare play do soldiers carry boughs cut from Birnam Wood to hide their advance?

Macbeth has been promised he is safe until Birnam Wood comes to Dunsinane Hill, so the army hidden behind branches fulfils a prophecy he thought impossible.

In The Lord of the Rings, the tree-like Ents of Fangorn Forest march out to destroy which stronghold?

Isengard is wrecked and flooded by Treebeard's army after the wizard Saruman's Orcs cut down many of Fangorn's trees. The Ents later replant the valley as a new forest.

Which Brothers Grimm siblings are abandoned in a forest and find a witch's house made of cake?

Hansel and Gretel was published in 1812 in the first Grimm collection. The witch means to fatten Hansel up before eating him, one of the darker plots in the nursery.

Which Dr. Seuss character confronts the Once-ler for chopping down the Truffula trees?

The Lorax was published in 1971 and is widely read as a fable about greed destroying the natural world, with the Once-ler standing in for industry.

Which giant logger of North American folklore is always accompanied by Babe the Blue Ox?

Paul Bunyan and Babe are said to have made the 10,000 lakes of Minnesota with their footprints. The tall tales began among real loggers before first reaching print in 1893.

In Norse mythology, what is the name of the immense sacred ash tree at the center of the Nine Worlds?

Yggdrasil is home to a squirrel named Ratatoskr, who runs up and down the trunk carrying messages between an eagle at the top and the dragon Níðhöggr gnawing at it from beneath.

Which huge, hairy creature of North American legend is said to roam the forests of the Pacific Northwest?

Bigfoot, also known as Sasquatch, is named for its supposed footprints, claimed to be up to 24 inches long. Some casts show claw marks, which suggests bears made them.

Which US Forest Service mascot has fronted a national campaign against wildfires since 1944?

Smokey Bear gained a living counterpart in 1950, when a three-month-old black bear cub was found after a wildfire in the Capitan Mountains of New Mexico and given his name.

Which holiday took hold in America in 1872, when Nebraskans planted about a million trees in a day?

Arbor Day in America was the idea of J. Sterling Morton of Nebraska City. The Spanish village of Mondoñedo had held a tree-planting festival much earlier, in 1594.

Which Kenyan activist founded the tree-planting Green Belt Movement and won the 2004 Nobel Peace Prize?

Wangari Maathai started the movement in 1977, and it has since planted more than 51 million trees. She was the first African woman to win the Nobel Peace Prize.

Under which president was the US Forest Service created in 1905, with Gifford Pinchot as its chief?

Theodore Roosevelt went on to establish 150 national forests, and the land he placed under public protection totals about 230 million acres.

Which traditional woodland practice cuts a tree down to its stump so that it sends up a crop of new shoots?

Coppicing leaves living stumps known as stools. The new shoots grow for a number of years and are then harvested, and the cycle begins again, so one tree can be cropped many times.

Which tree-dwelling rainforest mammal has green algae growing in its shaggy fur as camouflage?

Sloth fur has grooved hairs that host the algae, hiding the animal from jaguars, ocelots and harpy eagles. The algae also feed sloth moths, some species of which live only on sloths.

Which butterfly flies south to spend winter clustered in the mountain fir forests of central Mexico?

Monarch clusters roost each winter in the oyamel firs of a reserve on the border of Michoacán and the State of Mexico, where the dense forest shelters them when temperatures fall to freezing.

Koalas, which sleep up to twenty hours a day, live almost entirely on the leaves of which tree?

Eucalyptus leaves are low in nutrition and contain toxic compounds that deter most other mammals from eating them, so koalas have the menu largely to themselves.

The milky latex tapped from the trunk of Hevea brasiliensis is the main natural source of which material?

Rubber trees are native to the Amazon basin, but they have been planted so widely that they now grow right across the tropics.

Which African tree with a hugely swollen trunk is widely nicknamed the upside-down tree?

Baobab trunks swell and shrink with the rains, a sign that they may store water inside. In some places people even use the trunks as reservoirs.

On a mountainside, what name is given to the edge beyond which it is too cold and harsh for forest to grow?

Tree line growth is sparse, stunted and deformed by wind and cold. The dwarfed, twisted shrubs at the very limit are known as krummholz, a word meaning 'crooked wood'.

Which US national park saw 36 percent of its area burn in the huge wildfires of 1988?

Yellowstone had received only 31 percent of its normal snowpack the winter before. In September 1988 the whole park was closed to non-emergency personnel for the first time in its history.

Orchids and bromeliads that perch on rainforest branches without feeding off the tree are known as what?

Epiphytes use their host only for physical support and draw moisture and nutrients from air, rain and debris. A single rainforest tree may carry several tonnes of them.

Which pigments, made fresh as summer ends, turn the leaves of temperate broadleaf forests red and purple?

Anthocyanins are not in the leaf through the growing season: the tree actively makes them toward the end of summer from sugars in the leaf, and bright light spurs the process.

Which once-dominant tree of Appalachian broadleaf forests was devastated by a fungal blight from 1904?

American chestnut losses are estimated at three to four billion trees. Shoots still sprout from surviving stumps, but the blight returns before they grow tall, so the species is called functionally extinct.

What is the botanical term for the way a broadleaf tree cuts off and drops its leaves before winter?

Abscission comes from Latin words meaning 'away' and 'to cut'. Before a leaf drops, the tree grows a protective layer of cells beneath the break, sealing the wound in advance.

Which invasive soil animals had been missing from North America's northern forests since the last ice age?

Earthworms from Europe and Asia eat through the thick layer of decaying leaves that the native forest plants evolved with, so their spread can leave young plants struggling and cut biodiversity.

What term describes a season when beech, hickory and other nut trees all produce a bumper seed crop together?

Mast year feasts send mouse numbers soaring, and the extra white-footed mice have been shown to raise cases of Lyme disease, because the mice host the ticks that carry it.

Great Smoky Mountains National Park, rich in broadleaf forest, is called the world capital of which amphibians?

Salamanders of up to 31 species live in the Smokies, representing five of the world's nine families. The red-cheeked salamander is found nowhere else.

Which bird of eastern North America's broadleaf forests once flew in flocks of billions but died out in 1914?

Passenger pigeon numbers once reached an estimated three to five billion, and one flock in 1866 took 14 hours to pass overhead. The last bird, Martha, died at the Cincinnati Zoo.

Which game bird of North America's broadleaf forests is among the heaviest flying birds in the world?

Wild turkey numbers had plummeted by the start of the 20th century through overhunting and habitat loss. Despite their bulk, the birds fly strongly over short distances and roost in trees at night.

Timber from broadleaf trees such as beech and walnut is classed as which type, whatever its true density?

Hardwood simply means wood from a flowering tree, so the label says little about strength. Densities vary so widely that some hardwoods are softer than most softwoods.

Which bird drills into tree trunks and pulls out insects and larvae with a long, sticky tongue?

Woodpecker tongues are anchored by a bone so long that it winds around the outside of the skull, which lets the bird flick its tongue far beyond the tip of its bill.