Forestry mulching starts fires. Here's what pays when your machine is the one that burns.

The honest answer is that a mulcher fire is two claims, and most contractors are only insured for one of them. The machine that burns is your own property, which means it’s an inland marine claim on your contractors equipment policy at whatever value you scheduled. The fire that leaves the lot and takes the neighbor’s fence, their shed, and a fire district’s suppression bill is a general liability claim. The diesel that ran out of the wreck into the dry creek bed is a third thing, and under most standard forms it’s nobody’s. Here’s how each one plays out on a tracked forestry mulcher in a stand of lodgepole in August.

Why a mulcher burns

A tracked mulcher is a diesel engine, a hydraulic system running hot, and a spinning drum with carbide teeth, all working inside a cloud of shredded wood that packs into every flat surface on the machine. Chips pile against the exhaust and the turbo. Fines settle on the belly pan. A tooth hits a rock in decomposed granite and throws a spark into cured grass. Any of the three lights a fire, and on a windy afternoon in South Park it doesn’t stay small.

That’s not a knock on the machine. It’s what the work is. Underwriters know it, which is why “do you do any forestry mulching” is a question on most equipment and GL applications for excavation contractors, and why the answer changes how the account is rated. Say yes if you do it. A claim on a policy that was written for a skid steer that “does a little brush work” is where the trouble starts.

Claim one: your machine

Fire is typically a covered cause of loss under most contractors equipment forms, including fire that starts in the machine itself. So the question isn’t usually whether the policy responds. It’s what the check is worth.

The scheduled value. Equipment policies pay based on what you told the carrier the machine was worth, subject to the valuation clause (replacement cost or actual cash value). A tracked mulcher scheduled at the number from three years ago, or scheduled as a bare carrier without the head, produces a check that doesn’t buy a mulcher. The 2019 values article covers this in detail, and mulchers are the worst case because the head can be worth as much as the machine under it.

The attachment. Some schedules list the carrier and treat the mulching head under an unscheduled attachments limit meant for buckets and forks. That limit rarely replaces a head. If the head is a separate line item on the schedule, it’s covered at that number. If it isn’t, ask.

What’s around the machine. Debris removal, the cost to get a burned carrier off a slope above Breckenridge, and rental of a replacement while yours is being settled are handled differently form by form. Some include them as small sublimits. Some don’t. This is a read-the-form line, and it matters more on a mountain lot where the recovery is its own job.

What the equipment policy typically doesn’t do. Pay the neighbor. Pay the fire district. Pay the fuel cleanup. It covers your iron and nothing else, which is the whole point of it.

Claim two: the fire leaves the lot

The neighbor’s trees, their outbuilding, their fence, the melted siding on a cabin, and the fire protection district’s bill for the engines that came out are all third-party property damage. That’s general liability, and under most standard forms it typically responds, subject to the limits and the policy language.

Two things make this claim different from most GL claims a dirt outfit sees.

The first is the number of claimants. A fire that runs a quarter mile through a subdivision in the wildland-urban interface doesn’t produce one neighbor with a claim. It produces every neighbor, plus the district, plus sometimes the state. A $1M occurrence limit is one number for the whole event. The umbrella exists for exactly this, and fire-mitigation contracts increasingly ask for one.

The second is fault. The neighbor doesn’t have to prove much. Your machine was running, the fire started at your machine, and the fire went to their land. What the carrier’s defense counsel will want is proof you did what a careful operator does: extinguishers on the machine, a water source on site, no mulching in red-flag wind, a spotter, and a written fire plan if the contract called for one. Those don’t change whether the GL responds. They change how the case gets argued and what it costs.

Claim three: the fuel

The saddle tank splits when the carrier goes over on its side, or the fire burns through the hydraulic lines, and forty gallons of diesel and hydraulic fluid go into the ground. Under most standard GL forms that’s a pollution exclusion, and it’s broad. The neighbor’s burned trees are GL. The diesel in the creek is a contractors pollution liability claim or nobody’s, depending on whether you bought that policy.

On a mulching account we typically look for a pollution form alongside the GL, because the exposure is sitting in the tank of every machine on the job. Whether the carrier offers it as an endorsement or a separate policy depends on the market, and the wording between the two is not the same.

The WUI makes all three bigger

Most forestry mulching in Colorado is defensible-space work: thinning ladder fuels around cabins and subdivisions in the wildland-urban interface. That’s the same terrain where a fire has the most to burn and the most people to burn it near.

The practical effect on your insurance: a fire mitigation contract from a homeowner, a fire district, or a county program commonly asks for general liability with the owner as additional insured, auto, comp, and a fire-prevention plan. The underwriter is going to ask the same things the contract does. Where you work, how close to structures, what season, and what’s on the machine to put a fire out.

What we don’t control

Whether the carrier calls the machine a total loss, how the fire district bills, and how the neighbor’s attorney counts trees. What we can do is make sure the mulcher is on the schedule as a mulcher at a real number, whether the GL form has the limits the terrain calls for, and whether the fuel is insured at all. If you’re not sure of any of those three, that’s a policy review.

Where to go from here

Pull your equipment schedule and find the mulcher. If the value is the purchase price, if the head isn’t listed, or if the word “mulcher” doesn’t appear anywhere on the policy, send the dec pages and the schedule through the policy review and we’ll mark what a fire would actually pay. If you’re clearing on the land-clearing and forestry mulching side of the trade and starting fresh, we’ll want to know what’s on the machine before we talk about anything else.

Serving businesses located in Colorado. Coverage is determined by the policy language and the carrier.