Onauru Trees

World trees, also called Onauru trees, dominate the Eternal Forests and the Evergreen Peninsula, but singular world trees can still be found all over the world, albeit rarely.

The Word Onauru-Tree is actually a misnomer. Onauru is the word elves use to describe themselves, and means nothing but Tree-People (Ona-uru). Onauru Trees would therefore tanslate as Tree-People Trees. The Elves (mostly the Norn) won't get tired pointing this out as a misnomer, but at the same time thank the humans for accepting the elvish claim in regard to the trees.

Basic Information

Anatomy

Surface Morphology

Onauru trees grow up to a height of 2400 ft (800m). The Main Trunk can have diameters of up to 62m and a circumference of roundabout 200m.
World tree branches spread out far and leave a lot of space in between. With lone world trees its lower layers thus receive more sunlight, whereas in world tree forests, neighboring worldtrees often take up that space with their own branches, forming the famous branching Labyrinths.
Both cases however support the world trees growth and health, either by allowng the tree to generate more nutrients on its own, or by forming a symbiotic Fae support network with the neighboring trees, in which all trees profit from the surplus Fae which each of them produces.
World tree branches can grow on every height, but those who cannot receive sunlight anymore are shed in younger age, provided the branches haven't turned into ironwood yet. In the Eternal Forests , the lower 200 meters rarely have any of them, except in the rare cases when one of them managed to grow upwards so high as to reach into the sunny areas.

Watertransport

Unlike smaller trees, the Onauru can't rely on the evaporation process in its leafs alone to create enough pressure difference for water to be pulled up the entire stem. Instead the tree is interspersed with small water caverns, which are filled with water by their surrounding cells once those recieve water. These caverns serve as an intermediary reservoir, from which water then can be transported further up. Several physical processes like Osmosis support the watertransport towards these caverns and through Onauru trees. World trees, where possible, often take salts from the surrounding area to help with this. The Trees are not dependent on these however, as, in absence of these salts, the trees own proteins could facilitate the transport. Depending on the regionally available salts , Onauru wood, at least those parts which burn still and haven't turned to ironwood yet, oftentimes burns in different colors than normal wood, usually more yellowish, violet, or red.

Ironwood

Once a tree reches a certain height, normal wood wouldn't be able to support the accumlated weight. Hence, in the lower layers, which carry the brunt of the weight, the outer shells of the tree begin to harden and store iron, which leads to enhanced stability. This wood is called Ironwood, and, if pulled from the living tree, outperforms even steel in its sturdyness and flexibility. Only the outer layers of the tree are made of this ironwood, forming an exoskeleton, while the inner core of the stem remain of softer nature to support the transport of nutrients and water. Ironwood still retains some functions, like the ability to transport water from the outside to the inside, and as some of the stabilizing structures oxidate, takes on a red color. The lower layers of World Trees hence take on a deep reddish brown coloring which slowly transfers into a more greenish and alive one the closer one gets to the crown.
Ironwood is incredibly hard to harvest, except by magic means, as axes tend to get dull, except if strengthened by Fae.

Layers

Contrary to common belief, the "seven layers of a world tree" are not a feature of the world tree but an emergent feature of world tree forests. Singular world trees, due to the way they branch, allow sunlight down to reach heights, which, in world tree forests, would be cast in everlasting dim shadow already. To describe these insular trees the concept thus makes no sense. The separation into layers of different biospheres can best be seen in the Eternal Forests.

Subsurface Morphology

The Surface of the roots is made of the sturdiest Ironwood, but of course retains "soft" inner parts to facilitate the transport of water, nutrients and building material. Onauru roots dig deep and far, both to facilitate stability and also to provide the massive tree with enough ressources. The root system reaches into depth of down to 300m (900ft) below ground, and reach out to a distance of about 800 meter (2400 ft), where they, similar to the branches, leave enough space in between for the roots of other world trees, which, if present, form root networks as the roots grow together.

World tree roots, due to their Ironwood nature penetrate the hardest rocks, which, as they grow, is slowly dissolved and used within the tree as building material.

Genetics and Reproduction

It is not known if World trees can die of old age, as no one ever witnessed that, but as they do have a way to procreate, it is surmised they do.

World trees are hermaphrodites, and can produce pollen as well as fruits, but change their role depending on their relative location. Only those trees which are located in exposed places, like at the rim of the world tree forests, or when they stand alone, actually produce fruit, while those trees in the middle of the Eternal Forests and the Evergreen Peninsula produce pollen, which is carried away by the wind.
World trees bloom and produce pollen every 25 years, and trees which are part of a Fae and root network, like the Eternal Forests, which forms an especially giant one, bloom at the same time. This leads to world tree pollen clouds every 25 years, which cover large parts of Orom, the Sea of Sand and the Cityleague of Eridu in bright orange.

Due to the Faebirth nature of world trees, it's pollen can be considered partly as fauna and is equipped with enough "intention" to facilitate the fertilization. This is even "visble" through the human sense for magic, such that, if looked at by humans in that way, makes it glow in a faint orange tinted light.

World tree pollen are also a powerful aphrodisiac and a sought after ingredient for love potions.

Sterility

Despite their best efforts to procreate, most world tree fruit are sterile. No one knows why, but sages presume it has something to do with the Cataclysm. Only one in about 100000 fruits carries a living core, from which another World tree can spring. Such a core is hence a kingly gift to any elf, and well sought after by the Norn of the Norn Empire, yet also the Church of the Creator, which seeks to destroy them.

Growth Rate & Stages

World trees grow EXTREMELY slowly. Considering the Umtyaheluk world tree of Amn, which is thought to be about 6000 years old, and which reaches only 400 meters, and hence half as high as fully grown world trees, it is presumed that it takes a World tree to grow to full size roundabout 12000 years. Sadly, because of the Plaguestorms and the Dark Times, there are no records about the way these trees grow.

Ecology and Habitats

World trees are extremely resiliant and can grow in cold and warm climates alike, although they much prefer warmth. They also grow in heights of up to 3 kilometer above sea level, as seen in the eternal forests and in the Norn Forests. Their relative scarcity despite this hardiness can only be explained by the Cataclysm and the World tree sterility.

Additional Information

Uses, Products & Exploitation

Ironwood is a sought after material which can only be harvested by druidic or other magically enhanced means. Norn prefer it to craft their weapons from, but also use it for jewelry and other things.

The Cryst flower, which grows in the canopy of the world tree, is the source of the drug Cryst, which is a sought after ability enhanceing drug for all kind of arcane and occult casters, but also necessary paraphernalia for the process of "curbing", in which aspiring arcane or occult casters, which are deemed unfit to face their Nemesis Fiend, are robbed of their ego to prevent them from turning into abominations.

Geographic Origin and Distribution

World tree grow all over Ardu, yet in larger populations only in the Eternal Forests and on the Evergreen Peninsula. Everywhere else only solitary world trees are known.

Symbiotic and Parasitic organisms

World trees are host to a plethora of parasitic and symbiotic species, like for example the parasitic Cryst-flowers and the Yago-Bush which produces delicious berries, that are also a sought after ingredient for healing potions.

In the dimmer areas further down the tree Bedshrooms grow. These are actually symbiotic and not parasitic and known to produce antidotes and cures to many an affliction, yet also, depending on size, serve as beds or meeting places for elves (hence the name).
Worldtrees are also home to parasitic and symbiotic fauna, like giant Woodlouses, and Onatermites which inhabit all those heights of a world trees where the wood still has a softer consistence than Ironwood.
Elves have their ancestral home on World trees, and are considered to live in a symbiotic relationship with them, as do their riding mounts, the draconic Draks.

Onauru Tree by cyrgan

Average Height

800m / 2400 ft

Average Weight

4 to 5 Mio ton