In short: A tree shear is a jaw-type attachment that cuts through tree trunks and brush hydraulically while holding onto the cut material. It makes clearing work faster and safer than cutting by hand with a chainsaw.

What is a tree shear and how does it work?

The shear has a sharp cutting blade and a jaw that closes hydraulically. The tree or brush is grabbed, cut through in a single motion, and the attachment holds onto the cut material until you place it where you want. This way the tree doesn't fall unexpectedly, and the material can be moved on in the same motion.

When is a shear useful for clearing?

Large-scale clearing: clearing trees and brush from a plot, route or quarry area before construction work.
Power line and pipeline corridors: removing trees along a route where cutting by hand would be slow and dangerous.
Dense, overgrown areas: where working with a chainsaw is slow and dangerous due to dense, uneven vegetation.

Unlike hand tools, a shear is operated from the excavator's cab, so the operator doesn't need to be right next to the tree being felled - this significantly reduces the risk of a workplace accident.

Shear vs. grapple

A shear cuts the tree down, while a grapple lifts material that's already been cut. On larger sites both are often used together: the shear fells the trees, and the grapple collects and stacks them.

What should you check when choosing?

Cutting diameter: must match the typical trunk thickness you're felling.
Machine hydraulics and weight: the shear needs a proper hydraulic flow, and the machine must be large enough for the attachment's weight.
Quick coupler: compatibility with the machine's quick coupler is the same as with other attachments.