Creativerse worlds are not "procedurally" generated, instead the program uses 4 template worlds and will randomly choose one of these whenever a player starts ("creates") a new world.
A large number of trees is/are part of each of these worlds which can always be found on the exact same spots "grown" in the exact same size on each copy of one specific template world.
Trees consist of Wood (a very useful resource block and crafting material), Leaves (can be used as Fuel or to build), tree Flowers, sometimes Beeswax and/or Queen Bees that can be "grown" into Beeswax when being placed, sometimes Vines (Cragwood and Wildwood trees) or patches of Moss on their trunks (Ashenwood and Weepwood).
Trees cannot bear fruit in Creativerse.
To harvest the blocks or materials that trees are made of, no Power Cells need to be equipped.
If you equip a Wood Mining Cell (or a Charged Wood Mining Cell) then you will be able to harvest these blocks/materials a bit faster than without wearing any Power Cells, but these weak Mining Cells will lose durability.
Stone Mining Cells or even better Power Cells will not lose any durability when harvesting vegetal natural blocks/materials, and they will speed up the harvesting process significantly as well.
In Creativerse Leaves or other parts of trees will not fall to the ground and (different from the original unmodded version of Minecraft) Leaves will not decay by themselves even after all blocks of Wood of the tree have been removed. This is because leaves are not just decorative stuff in Creativerse, they are also useful as Fuel and building materials (like for floors of player-made arenas to make specific Creatures, tree Flowers, Beeswax or Treasure Chests spawn).
To get rid of whole trees faster, you can use Excavators to remove 7x7x7 blocks of any natural material, and half of these blocks will be saved in loot bags.
Currently (as of R38 in January 2017) you can find 9 different kinds of trees on any new Creativerse world:
- chestnut-brown Cragwood trees with dark green leaves and Yellow Flowers in Forests, Woodlands and Grassland biomes. Can be found in all sizes from tiny bush-like piles to very tall and large specimen (with trunks of 8x8 blocks). On tall or self-grown Cragwood trees patches of Vines may grow. By harvesting those you will often receive 1 block of Cragwood as well as 1x Vines.
- birch-like white Ashenwood trees with Red Flowers that can be found in Forests, Woodlands and Grassland biomes, as well as in valleys of Mountains. Can be found in bush-like sizes too (like on Canyon plateaus), in slender medium-size or in a thicker (trunks of 4x4 blocks) version at it's largest. Ashenwood-trees often have Moss growing on their stems, however not always. By harvesting these you will often receive 1 block of Ashenwood plus 1 block of Moss.
- pinetree-like Elderwood trees with very dark green leaves and Blue Flowers in Mountains, Tundra and (sometimes snowy) Taiga biomes. In snowy Taigas, Elderwood trees are often significantly larger. In cold areas Elderwood-trees might be snow-covered and/or even have whitened Snowy Elderwood Leaves that will turn into ordinary Elderwood Leaves when harvested though. Rarely you can find giant thick Elderwood trees that do not look pine-like but like foliage trees in Savannah biomes. They have hollow trunks and the ground around them is covered in Rimecones. On old worlds created before R14 Elderwood-trees also often came in the shaope of gigantic sequoia-like foliage-trees.
- palm-like Shorewood trees on beaches or in oasis' on Shores close to Ocean biomes with big bright green leaves and no blossoms at all. Shorewood is currently the only kind of wood where Queen Bees cannot be placed on. The rare Shorewood Husk is not some kind of Wood, even if it looks a lot like Shorewood; however it can be used as Fuel for the Forge
- colorful Autumnwood trees in the Forest biome with either red Cinnamon Autumnwood Leaves or yellow-brown Citrus Autumnwood leaves or brown Mocha Autumnwood leaves. All of these trees also feature some beige-white star-shaped Autumnwood Flowers, and can grow Beeswax occasionally too. The ground below Autumnwood trees is often covered with leaves which all turn into Mocha Autumnwood leaves when collected.
- Weepwood trees looking like weeping willows in Swampland biomes with emerald colored leaves and small yellow-green Weepwood Flowers. Weepwood trees are often covered in a lot of Moss and can feature Beeswax in their foliage as well.
- Wildwood from large trees in Jungle biomes with two different kinds of dark green leaves and also two kinds of pink and orange Wildwood Flowers in large amounts that brightly glow golden in the dark. Wildwood usually has a lot of Vines growing on it, especially the frequent giant Wildwood trees with snow on top that you can even spot on the map in jungle biomes. While the type of Wildwood Flowers that does not glow in the dark will turn into the common type of Wildwood Flower when being harvested, Dark Wildwood Leaves are a completely unique type of decorative Leaves than common Wildwood Leaves.
- medium-sized Parchwood trees with "flat" tree-tops in Savannah biome have golden leaves but no blossoms at all. In warmer areas of Savannahs you might be able to find Queen Bees that spawn on Parchwood Leaves but cannot turn into Beeswax there on their own because the environment temperature is too high for that.
- Corrupted Wood can be found on the Corruption layer underground which is (currently) the deepest layer of any Creativerse-world. Corrupted Wood grows in the shape of long branches and/or roots spreading all over the "cave"-ceiling as well as over the ground of the Corruption layer, and in 1-block-wide stems in between; sometimes sprouting into small to medium sized trees with bright purple corrupted leaves (without any blossoms nor beehives) growing from the branches/roots, also from under Corrupted Water or even hanging upside down from the ceiling.
If purified this natural Corrupted Wood will turn into Cragwood and Corrupted Leaves will turn into Cragwood Leaves when purified.
Additionally to that you can grow trees from Saplings whereever the conditions are fitting (best in Woodland and Forest biomes) on a block of Grass or Dirt (can be placed by you too) with a bit of water nearby.
Wood is flammable, so caution is adviced when putting torches onto or especially directly under blocks of Wood or Leaves, especially in hot environments like Savannahs, Shores or Jungles. In hot Biomes fire can spread quickly onto other flammable materials and even "jump" over small gaps of 1-2 blocks as well as burn through flammable materials under water.
Fires cannot be stopped (currently, as of R38 in January 2017) except by creating aisles/swathes wide enough to prevent flames from spreading over or by disabling the spreading of fire for the world, or by quickly claiming the area and disabling the spreading of fire there. Please note that wooden furniture and many building-blocks crafted from wood are flammable too, so a wooden ladder or even fort can be consumed by spreading fire in the worst case. Such a whole forest and/or a wooden house can burn down completely to nothingness if the fire is not stopped in time.
"Pro" players can disable the spreading of fire on their whole worlds though, and owners of Claims can also disable the spreading of fire on each of their claims. If the spreading of fire is disabled for a world, then it can still be enabled on claims.
Wood is prone to corruption spreading. This means by placing any corrupted block or Corrupted Water next to a block of Wood (like by touching the trunk of any tree) the adjacent block of Wood will turn into Corrupted Wood, and will next "infect" more adjacent blocks of Wood until the whole trunk and some branches of the tree will be corrupted. It takes a while for this process to finish though, and will take longer if no player character is nearby. Any block of moss-covered wood will also turn into Corrupted Wood.
Leaves can be corrupted too (except for Parchwood leaves), but only by throwing Corrupt Bombs at them, as they are immun against the spreading of corruption. Tree Flowers, Vines, Beeswax and Queen Bees cannot be corrupted at all.
Any kind of Wood or Log can be used as Fuel for the Forge, also Leaves can be used as Fuel, however 2 blocks of Wood or 4 blocks of Leaves will be needed for each process (of melting or hardening), and they will burn rather slowly.
As mentioned, Wood (but not Logs) and Leaves can be corrupted and such turned into much better Fuel that will burn significantly faster than the uncorrupted types, but these block will require Lumite Mining Cells to harvest.
Mind that some crafting recipes will accept many different types of Wood blocks alternatively that you can scroll by clicking on their icons that feature two small golden arrows below in your Crafting Menu (default key "Q") or at Crafting Table (that still exist in old worlds). Also tree Flowers are a frequent crafting ingredient for many products.
Tree Flowers can be turned into Pigment in a Processor: Yellow Flowers from Cragwood trees into Yellow Pigment, Red Flowers from Ashenwood trees into Red Pigment and Blue Flowers from Elderwood trees into Blue Pigment.