The five differences that account for most of the gap

Finish standard, retained vegetation, material handling, stumps, and access. Each of them can change the hours on a site substantially, and each is easy to leave implicit in a conversation.

A finish standard is the most common. 'Cleared' can mean anything from stems knocked down and left, to a mulch mat processed fine enough to mow over. Those are different jobs with the same one-word description.

What a comparable scope contains

  • The mapped work limit, with the boundary described by something physical rather than by acreage
  • What is retained — species, size, specific trees, or a mapped area
  • The finish standard, stated as a mulch depth or particle size rather than as an adjective
  • What happens to material: mulched in place, piled, chipped, or removed
  • Stumps: left, ground, or excavated, and what the surface must support afterwards
  • The access route, and who is responsible for its condition afterwards
  • Anything known to be in the ground: wire, stone walls, old foundations, culverts, buried services

Why the acreage number is the weakest input

An acre of open field with scattered saplings and an acre of dense fifteen-year regrowth with mature stems are the same number and not remotely the same job. Density, average and maximum stem size, species and entanglement drive the hours far more than area does.

That is why a contractor asks for photographs, and why a quote given from acreage alone is a guess that both parties will revisit.

How to read a much lower number

A low quote is sometimes a genuinely more efficient operation, and sometimes a narrower scope. The way to tell is to ask what it excludes rather than to ask why it is low.

Ask the five questions above of both quotes. If the low one turns out to cover the same work, that is useful information. If it turns out to exclude the access route, the stumps and the finish, then the two numbers were never comparable and the gap was never a discount.