"The nature flicker contained within this focus will seek out trees within a 6 block radius around their flicker habitat, once they do they lightning flickers will fell the tree one block at a time. These flickers can operate without a source of power but they are much faster when they have a source of etherium to fuel themselves."
When a felled oak flicker focus is placed in a habitat, it will detect any trees within a 6 block radius and chop them down starting from the bottom log, going up, and does not destroy the leaves of the tree(s).
To craft the felled oak flicker focus you need 2 Witchwood logs, 1 Binding catalyst, an axe, 1 Nature Flicker jar and 1 Lightning Flicker jar in the arrangement below. Do note that the flicker jar on the left is a Nature Flicker jar while the one on the right is the Lightning Flicker jar.
By placing a lightning flicker in a habitat next to the felled oak flicker focus habitat, it will make the process faster.
By placing a nature flicker in a habitat next to the felled oak flicker focus habitat, the flickers will also re-plant saplings which it gets from an adjacent chest (a chest beside it).
It is much faster to use a flat lands flicker focus to chop trees, in conjunction with the felled oak flicker focus with a nature upgrade.
When unpowered it will take 180 seconds (3 minutes) till it starts chopping down another tree and 15 seconds if powered.