Per acre when you've seen the ground and can class the density — landowners strongly prefer a fixed number, and a well-classed acre price protects your margin. Hourly ($150-$250/hr machine-plus-operator on a compact track loader) when scope is genuinely uncertain: mixed junk in the growth, no site walk possible, or the customer keeps adding 'while you're here' work. Never quote per-acre sight-unseen.
Mastiff is the one app for forestry mulching and land clearing companies — jobs, density-based quoting, invoicing, equipment, before/after showcases, and directory leads in one login.