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How much should you charge for forestry mulching?

The honest answer is that price per acre is not a rate, it is a quotient, and the reason is specific rather than philosophical. The machine is paid for by the hour. The acre is what the customer counts. What sits between them is your production rate — acres per machine-hour — and that number is not a property of the lot's size. It is a property of what is standing on it, and across the four densities people actually call about it moves by nine to one. This page prices one real job all the way through, then changes exactly one input to show the problem.

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The job

3 acres of an old pasture growing back in — medium brush, stems 2–4 inches with the odd 6 — on rolling but dry ground. A 75 hp compact track loader with a 6 ft drum mulcher. Operator cost $45/hr burdened, 5 gal/hr of fuel at $3.90, a $1,800 set of teeth lasting 250 hours, a $12/hr service reserve, a $2,400 monthly machine payment, $4,800 a year of insurance, and 70 billable machine hours in an average month. One round trip on the trailer: 2.5 hours and 70 miles at $1.35 a mile. Target margin 35%. Every figure below comes out of the calculator on this site with exactly those inputs.

1. Acres per hour, because it sets everything else

Start at the machine, not the parcel. The rate is swath geometry and nothing more:

acres/hr = head width (ft) × advance (ft/min) × 60 × cutting share
           ──────────────────────────────────────────────────────
                        43,560 × passes

A 6 ft head at 42 ft/min while cutting is 15,120 sq ft an hour if you never stopped and the ground were flat. You do stop — repositioning, fuel, walking the boundary, knocking mulch out of the head — so 80% of the hour is cutting; and rolling ground with stumps to steer around slows the advance, here 85% of the quoted speed. One pass. That is 0.236 acres an hour.

Two notes on that number. It is a model, not a measurement: if you have ever timed a finished lot, put your rate in instead and the calculator will tell you what advance speed it implies, which is a better sanity check than any published table. And the “share of the hour cutting” figure is the one people flatter themselves about — it is what separates a clean 5-acre rectangle from a wooded lot cut up by a creek and a driveway.

2. Rate becomes hours, hours become days

3 acres ÷ 0.236 acres/hr = 12.7 machine hours, which at eight machine hours a day is 1.6 days on site. Machine hours is the unit your costs are denominated in. It is also the unit a customer never asks about, which is the whole difficulty.

3. What one machine hour actually costs

The last two lines are the ones a hand-written quote leaves out, and together they are $47.20 of the $123.70 — more than fuel and teeth combined.

Teeth are a consumable, not a repair. A set is consumed over hundreds of hours and the bill arrives months after the jobs that caused it, with no job attached to it, which is exactly why it never makes it into a quote. Clean standing timber is kind to carbide; sand, rock and cutting near grade are not. If you are unsure of the life figure, halve it and look at the price again before you send it.

The payment is a utilisation number wearing a pricing number's clothes. At 70 billable hours a month it is $40.00 an hour — 32.3% of what the machine costs to run. At 160 billable hours the same payment and insurance are $17.50, the hourly cost falls to $101.20, and the same job prices at $2,297.32 instead of $2,737.29. If your per-acre number feels uncompetitive, check that figure before you cut the price: you may be looking at an idle-machine problem rather than a market one.

4. Mobilization is its own line, and that is not a formality

Loading, floating out, unloading, and reversing all of it: 2.5 hours at the operator rate is $112.50, and 70 round-trip miles at $1.35 for truck and trailer is $94.50. $207.00.

That $207.00 is the same $207.00 on a half-acre lot and on a ten-acre one, and this is where a flat per-acre rate does its quietest damage:

Same machine, same ground, same margin, and the honest per-acre price runs from $838.12 to $1,443.20 on nothing but lot size. Quote a single number across all three and you have overcharged the ten-acre job you wanted and underbid the half-acre one you now have to drive to. Once mobilization passes about a quarter of the price — which it does at half an acre here — stop quoting that job per acre. A day rate or a stated minimum charge is the honest shape for it.

5. The quote

That is $912.43 per acre, with $593.08 per acre as break-even and $958.05 of margin on the job.

Margin is not markup. A 35% margin means price = cost ÷ 0.65. Adding 35% to cost gives cost × 1.35 = $2,401.97, which is a 25.9% margin, not 35%. The gap is $335.32 on this one job, and it repeats on every job you ever quote. This is the most common arithmetic error in trade pricing and it always runs in the same direction.

6. Now change one number

You quote the next lot at the same $1,000 an acre without walking it, because the last one worked out. Same 3 acres, same machine, same costs, same quote — only what is standing on the ground is different:

$2,059.29 at the top and −$3,810.40 at the bottom: a $5,869.69 spread on one quote. The acreage never moved. What moved is that the same 3 acres is 5.9 machine hours of work in one case and 53.4 in the other — nine times the machine time.

Why it compounds the way it does is worth internalising, because it is two effects, not one:

• The advance speed falls. Heavier stems mean less forward progress per minute with the drum loaded — here 90 ft/min in saplings down to 30 ft/min in 8–12 inch material, a factor of three.
• And the pass count rises. Light material falls small enough on the first pass. Heavy material comes down standing on the first pass and the mat then has to be reworked, twice more here, to reach a particle size a customer calls finished. That is another factor of three, multiplying the first.

Three times three is the nine. A customer describing their lot on the phone cannot tell you which of these four rows they are in, and neither “it's a bit brushy” nor a satellite photo will settle it. Walk it.

7. What is not in the per-acre number at all

• Stumps. Mulching takes standing material down and leaves a mat. It does not remove a stump below grade. If the customer's idea of “cleared” includes grubbing, that is a different machine and a separate line.
• Stems above what the head is rated for. A 16 inch stem on a head rated to 8 is a felling job before it is a mulching job, and the time to drop it is in no production rate. Price those separately or exclude them in writing — forcing oversized material through the drum is how a day goes to teeth, a belt, or the drum itself.
• Everything the site says no to. Permits, burn rules, stream and wetland buffers, erosion control, protected species, property lines and buried or overhead utilities. None of it is arithmetic and none of it is in this tool. It is the part of the job that turns a priced quote into a legal one, and it is yours.

What to do with this

1. Quote the density, not the acreage. Write the stem size and the finish standard into the quote as named terms. A lot that turns out heavier than described is a change order, not a lesson.
2. Time yourself once. One finished lot with a start and a stop time gives you a production rate worth more than every published per-acre figure put together.
3. Put the teeth and the payment in the hourly rate before you divide by anything. They are $47.20 of $123.70 here and they are invisible per acre.
4. Use a minimum charge for anything under about an acre, because the trailer does not care how big the lot is.

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