Oak

An oak is the most common tree in the game, available in several variants. It has the smallest space initial space requirement for growth, and along with dark oak trees, it can drop an apple when a leaf block is destroyed.

Variants
Oak trees come in several variants with widely different properties: An oak tree with a unique arrangement of leaves is generated at meeting point 3, in plains villages. This leaf arrangement is not found elsewhere naturally, and it cannot be grown from a sapling.
 * 1) Small regular oak trees are the most commonly encountered. The leaves are arranged the same as the birch leaf arrangement.
 * 2) Large "fancy" oak trees are less common and have a distinct look and different growth requirements. They often have "branches", outgrowths of logs on the sides of the trunk, or even freestanding and surrounded by leaves. They require 4–14 blocks of open space directly above the sapling to grow (air or leaves only) but can otherwise be completely enclosed on all sides.
 * 3) * A fancy tree form exists with a single leaf block layer above the minimal 4-block trunk, rarely allowing a tree to grow in a vertical space with a height of only 5, but otherwise the maximum trunk height is 2 less than the vertical space, making the practical minimum height 6.
 * 4) * A tree can be forced into a fancy configuration if a "brace" of non-solid blocks (e.g. glass or slabs) is placed around where the trunk would be, one block off the ground.
 * 5) * A rare variant that is colloquially known as a "balloon" oak, which are fancy oak trees generated with the smallest size possible, may be grown. They consist of tall trunks and leaves that formed a spherical shape, similar to a balloon. They grow even if there is a block obstructing them; they simply grow around that block. They usually contain 4 blocks of logs, but some may contain more.
 * 6) In swamp biomes, naturally occurring oak trees tend to grow in the water. Unlike oak trees in other biomes, which typically have a slightly conical or pointed canopy, all swamp trees have round, flat-topped canopies. Also unlike other oak trees, these have a much wider range in foliage. They tend to be covered in vines that trail down to the ground.

Breeding
Oak trees require a 1×1 column of unobstructed space at least 4 blocks above the sapling to grow (5 blocks including the sapling itself). Oak trees are unique in that they can still grow when the base and trunk are enclosed on all sides. Their growth is not hindered by logs, leaves, dirt, and saplings.

An oak tree grown from a sapling within 2 blocks of a flower has a 5% chance of having a bee nest containing 2 bees.

Other variant oaks
$$, trees can generate as one of the two following variants of the normal tree. Both of these generate naturally, and can be grown out of normal saplings.



Dying trees
A dying oak tree has the standard growth pattern of any other tree, however, all exposed logs in the main trunk are covered with vines. They can generate as regular or small oak trees.

Fallen oak trees
These trees consist of a single upright log, or stump. Logs lying on their side are often found 1–2 blocks from the stump. They occasionally have mushrooms on top.

A fallen oak tree has a log length of 4–7 blocks, and the stump is 75% covered with vines.

Trivia

 * Large jungle trees and dark oak trees generate with dirt under them if they generate partly or wholly over air or water blocks.
 * In real life, oak is a genus of tree known as Quercus.