Update 2020-05-17: I had plans for a big overhaul to make it use robots to harvest trees and generally look much better than trees just disappearing. However Klonan's Mining Drones does pretty much exactly what I had in mind, so use that instead: https://mods.factorio.com/mod/Mining_Drones

If someone wants to take over this mod it is MIT licensed so you can do whatever you want with it.

A mod for Factorio to auto harvest trees from the world. Intended as an early-game help for clearing out forests and automating early wood gathering, not intended as a self-sustaining wood factory.

If you're looking for regrowing or plantable trees, check out the "tree-growth" or "treefarm" mods

Big thanks to eradicator on the Factorio forums for helping a newbie out.

--- Version 0.17.2 ---
Compatibility:
- Works with Alien Biomes

Bugfixes:
- Doesn't try to harvest itself or buildings around itself any more. Oops.

--- Version 0.17.1 ---

Compatibility:
- Updated to work with Factorio 0.17
- Mod should now work better when installed alongside other mods that modify trees such as BioIndustries, TreeFarm and TreeGrowth.

Changes:
- Harvesters no longer silently disable themselves when running out of trees to harvest, but mark themselves for deconstruction once all materials have been removed. (Can be changed in mod settings)
- Harvester recipe changed due to removal of iron axes, now only requires 5 gears and 10 plates.

Bugfixes:
- Harvesters now actually stop harvesting when marked for deconstruction, and won't refill the input slot while inactive.

Cosmetic:
- Major/minor mod version follows Factorio, so mod version 0.17.x is compatible with Factorio 0.17