Of the export shipments we have helped unpick after a port hold, bark is the most frequent single cause — ahead of illegible marks, ahead of untreated dunnage, ahead of post-treatment repair. It is also the most avoidable, which is what makes it infuriating.
What the standard says
ISPM-15 requires that wood packaging material be made from debarked wood. The standard tolerates small individually separated patches under a specified size, but the practical reality at an inspection point is simpler: visible bark invites a hold. An inspector with a queue and a judgement call will not spend ten minutes measuring your patch.
Why bark is the rule
The treatment requirement exists to kill pests in the wood. Bark is where many wood-boring insects live and lay, and it also insulates — the layer under bark may not reach core temperature even in a correctly run chamber. So the rule is not bureaucratic fussiness. A bark-covered board can pass through a compliant heat cycle and still carry living organisms.
Where it hides
- Bottom deck boards, especially outer ones. They are the least-inspected component and the most likely to be cut from lower-grade lumber.
- Stringer edges, particularly on repair plugs cut from offcuts.
- Blocking and dunnage inside the load. Loose bracing falls under ISPM-15 too, and it is frequently cut on site from whatever is around.
- Crate cleats and skid runners — the structural timber nobody thinks of as packaging.
- Repair boards added after treatment, which carry a double problem: untreated and possibly barked.
Our process, for what it is worth
Debark check happens before the chamber, not after, and it is a physical inspection of every face of every component by someone whose job that is. Platforms that fail go back to the repair line for board replacement. We would rather eat the cost of a rejected board here than have a customer's container sitting at Savannah.
If you are specifying export packaging
Write "debarked, ISPM-15 heat treated, marked on two opposite faces" into the spec, and add a line requiring that any post-treatment repair be re-treated and re-marked. That last clause is the one that saves people, because it closes the loophole where a compliant pallet gets fixed on a dock with an untreated board and silently becomes non-compliant.
And if a port does query a load: a batch record beats an argument. Ours is tied to the shipment reference and goes out with the packing list, so a query is an email rather than a week.
Why bark survives a correct heat cycle
The treatment requirement is 56 °C held for thirty minutes at the core of the wood. Bark is a poor conductor and an excellent insulator — that is its biological job. A board with bark still attached can sit in a chamber that genuinely achieved core temperature in its probed members while the layer under that bark lagged behind, and that layer is exactly where many wood-boring insects live and lay.
So the debarking requirement is not an additional box to tick alongside treatment. It is a precondition for the treatment to mean anything. A barked board in a compliant chamber is a compliant cycle around a non-compliant component.
What inspectors actually do
They have a queue and a judgement call. The standard permits small, individually separated patches within specified dimensions, and in a laboratory you could measure yours and argue. At a port, with a container on a clock, visible bark reads as non-compliant and the load is set aside. Being technically within tolerance is not a strategy when the cost of being wrong is detention and the cost of being right is an argument you have to be present to make.
The five places we find it on inbound stock
- Outer bottom deck boards, cut from the lowest grade lumber in the build and inspected by nobody.
- Stringer edges where a mill left a wane — the rounded original surface of the log, often with bark in the hollow.
- Repair plugs cut on a dock from offcuts, which is the most common route for bark to enter an otherwise clean platform.
- Crate cleats and skid runners, which people do not think of as packaging and which fall squarely under the standard.
- Loose blocking and dunnage, cut to length on site from whatever was lying around.
The clause that protects you
Put this in your packaging specification: any repair, modification or supplementary bracing applied after treatment must use debarked, ISPM-15 treated material, and the unit must be re-marked. One sentence. It closes the loophole where a compliant platform gets fixed on a dock with an untreated, possibly barked board and continues to carry a mark that is now void.
We apply the same rule internally, which is why debarking inspection happens before the chamber and board replacement happens before treatment rather than after. It costs us rejected boards. It is considerably cheaper than a customer's container sitting at Savannah.
Marcus, yard supervisor · Pallets Recycle, 1113 Ingram Ave, Richmond VA · published April 2, 2024 · 824 words. Corrections welcome — tell us if we have this wrong.