This area must be open, flat, and large enough to fit the farm. If your location does not fit these requirements, you can flatten an area yourself.

Trees need at least a 3x3 space to grow properly.
Trees can only be planted on dirt or grass. Therefore, a tree farm cannot be in a nether, mesa, desert, or tundra biome.
 Use fencing to enclose your farm area. Don't forget to build an entrance. Enclosing your farm will prevent hostile mobs from entering and make the farm look neater in general., Saplings are obtained by breaking leaf blocks with anything but shears. Trees won't always drop saplings, so remember, be patient if you need a large quantity of saplings., Place the saplings, so that there are at least 3 blocks between each sapling., If you would like to speed up this process, you can place bonemeal, gathered from bones of a skeleton, on the saplings., Chop down the trunk first with your axe, then break the leaves with anything but sheers to collect more saplings and other drops. Continue chopping down all the trunks and leaves.,
Find a good spot to make a tree farm.
Enclose the tree farm.
Gather saplings.
Plant the saplings.
Wait until all of your trees have grown.
Chop all of trees at once.Repeat the planting and gathering steps to make an efficient tree farm.
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