Treesfall
From Zedwiki
Treesfall
Zurvival's treesfall plugin helps with preventing floating trees, and with farming wood. When the player breaks a log, the plugin looks for logs from the same tree, and makes them fall like sand/gravel. The plugin only affects logs that are above blocks that trees can be grown on - dirt, podzol, grass, etc - so as to prevent player builds being affected.
Toggling
Using /treesfall, the player can toggle the effect for logs they mine. This can be useful if they wish to climb taller trees, such as jungle or spruce, or if they're building using logs over dirt-like blocks.