What each pricing structure actually measures

The pricing format is not a detail of presentation. It determines who carries the risk that the site turns out to be harder than it looked.

Published by the Land Clearing Authority editorial team · Last revised 2026-07-29 · Editorial policy · Corrections

Who this is for

Anyone comparing bids that use different pricing formats
Landowners with a site that cannot be fully assessed in advance
People trying to work out whether an hourly quote is a warning sign

The short answer

Per-acre pricing measures enclosed area, which is not the workload. It works where growth is uniform and assessable, and it misleads where density or stem size varies across the parcel.

Hourly pricing measures machine time, which is the workload. It transfers the risk of an unexpectedly hard site to you, and it is the honest structure where the site genuinely cannot be assessed.

Lump-sum pricing transfers that risk to the contractor, who prices it accordingly. It buys certainty and you pay for the contingency whether or not it is needed.

None is inherently better. What is wrong is a lump sum presented as precise on a site nobody could see into, or an hourly rate with no estimate and no checkpoint.

What changes the answer

How well the site can be assessed before work starts
How uniform the growth is across the area
Whether concealed obstacles are likely
How much certainty you need for your own budgeting
Whether the scope is likely to change once work reveals the ground

The three structures compared on risk

Read the risk column first. That is the substantive difference between the three.

Pricing structures, what they measure, and who carries the uncertainty
Structure	Measures	Risk sits with	Suits
Per acre	Enclosed area	Shared, badly	Uniform, open, assessable growth
Per hour	Machine time	The owner	Unassessable sites, reclamation, unknowns
Lump sum	A defined outcome	The contractor	Well-defined scope on a visible site
Per corridor length	Linear distance	Shared	Trails, fence lines, access routes
Per stump or unit	Countable items	Shared	Discrete, countable work

Why per-acre pricing misleads

It is the most commonly quoted structure and the least connected to what actually drives cost.

The workload in clearing is fibre volume — how much woody material has to be cut, and how large the individual stems are. Two adjacent acres can differ by a large multiple in fibre volume while being identical in area.

So a per-acre rate is really a rate for an assumed density and stem size. When the assumption holds it works well and it is easy to compare. When it does not, one party is going to be unhappy, and which one depends on which direction the assumption was wrong.

The way to use a per-acre figure is to ask what density and stem size it assumes, and what happens if the parcel differs. A contractor with a clear answer is pricing; one without is guessing.

How to make hourly pricing safe

Hourly is frequently the right structure and it needs three conditions to be safe for the owner.

An estimated range, with the assumptions behind it stated.
A checkpoint — a number of hours at which work pauses and you both reassess.
Clarity on what is inside the hour: is travel charged, is setup, is refuelling, is the second operator.
A definition of the day: how many hours, and what happens to a part day.
A written note of what you agreed, because hourly disputes are memory disputes.

What you are paying for in a lump sum

Certainty has a price and it is worth knowing what you are buying.

A contractor offering a fixed total is accepting the risk that the job takes longer than they expect. Rationally they include contingency for that, sized by how uncertain they are. On a clear, visible, uniform site the contingency is small. On a heavily overgrown parcel it is large, and you pay it whether or not the site turns out to be difficult.

That is not unfair — it is the cost of the risk transfer. It does mean that on a genuinely unknown site, a lump sum is usually the most expensive way to buy the work, and the way to reduce the price is to reduce the uncertainty rather than to negotiate the number.

Opening a small area first is often worth more than any amount of haggling, because it converts contingency into knowledge.

Comparing bids in different formats

This is the practical problem, and the answer is to stop comparing numbers and start comparing described work.

Ask the hourly bidder how many hours they expect and what that totals. Ask the lump-sum bidder exactly what is included and what is excluded. Ask the per-acre bidder what density their rate assumes. Now all three describe the same thing and the numbers can be lined up.

Then check the scopes match on the four questions that actually move price: what happens to the standing growth, where the material goes, what happens below the ground line, and what the surface will be like. Bids that differ on any of those are not competing offers.

Where a bid is much lower, the explanation is nearly always in one of those four answers rather than in efficiency.

What drives the cost

Cost drivers on this kind of project
Driver	Effect
Site assessability	Determines how much contingency any fixed price has to contain.
Growth uniformity	Uniform growth makes area-based pricing reasonable; variable growth does not.
Risk allocation	Whoever carries the uncertainty prices for it. Certainty is never free.
Scope definition	A vague scope makes every format unreliable, including lump sum.
Mobilisation and travel	Inside or outside the quoted unit — frequently unstated.

Common mistakes

Comparing a per-acre rate against a lump sum without normalising the scopes
Accepting an hourly rate with no estimate and no checkpoint
Reading a low lump sum as efficiency rather than as a narrower scope
Not asking what density a per-acre rate assumes
Assuming travel and setup are inside the quoted hours

Questions to ask a contractor

What density and stem size does this rate assume?
How many hours do you expect, and at what point would we reassess?
Is travel, setup, and refuelling inside the hourly rate?
What is expressly excluded from this total?

What to do next

Ask every bidder to describe the scope in outcome terms before you look at price
Convert all bids to a comparable basis — expected total, with assumptions
Where the site is unassessable, consider opening a small area first
Use the quote comparison tool to line up the bids you hold

Questions people actually ask

Is hourly pricing a red flag?

No. On a site nobody can assess it is the more honest structure, because a fixed price would be a padded one. What matters is that it comes with an estimated range, a stated basis, and a point at which you both stop and reassess.

Why will nobody give me a per-acre price over the phone?

Because area does not determine the workload. A contractor who quotes per acre without seeing the growth is quoting an average of their previous jobs, which tells you about those jobs rather than yours.

Should I always take the lowest bid?

Only once you have confirmed the bids describe the same work. Most large gaps come from a difference in one of four things: standing growth, material destination, below-grade work, or finished surface. Find the difference before deciding.

Can I ask for a mix of structures?

Yes, and it is often the best answer. A fixed price for the parts that are visible and assessable, hourly for the parts that are not, with a checkpoint between them. Most experienced contractors will structure it that way if asked.