Back in the day, humans chopped down forests the old-fashioned way: lumberjacks with axes. Obviously, a 9072kg monster with tank treads and massive saws mounted on a crane does the job harder, better, faster, stronger.
This is the EcoLog 590D. It's designed to down trees in rugged terrain, strip them of their branches, and chop them into segments in a matter of seconds. The hulking rubber tires can be wrapped in tank treads for extra traction, and the front wheels come with a "balanced bogie option" that will hoist the machine a few extra feet into the air. With the spotlights blazing, it's the epitome of the deforestation monsters you might see on a good episode of Captain Planet. EcoLog maintains that it's committed to the environment.
GIF by Andrew Liszewski.