The regional table / Washington
Cedar-Planked Salmon
Nearly everything written about planked salmon gets two things wrong: that the plank is there for flavor, and that the fish is done when it flakes. The plank is a heat shield that happens to smoke, and by the time a king salmon flakes freely you have cooked its fat out onto the board.
Two eyewitness documents sit under this dish, and neither of them puts a board under the fish. The first is James G. Swan, The Northwest Coast; or, Three Years' Residence in Washington Territory, Harper & Brothers, 1857, pages 108 and 109, describing a breakfast he was given at Chinook on the lower Columbia. The salmon, he writes, is "cut into large, flat slices, with skewers stuck through to keep them spread; then, placed in a split stick, as a palm-leaf fan is placed in its handle", the ends of the stick tied with a wisp of beach grass and the whole thing "thrust in the sand firmly and at the right distance from the fire, so that the fish can roast without scorching", with clam shells laid underneath to catch the oil, "which will run from these rich, fat salmon almost in a stream". The second is Hermann Haeberlin and Erna Gunther, The Indians of Puget Sound, published in 1930 as Volume IV, Number 1 of the University of Washington Publications in Anthropology, which records the same frame among the Coast Salish of the Sound: "One of the most popular ways of preparing fish was to roast it on a stick over the fire." A stick about two feet long, split for three-quarters of its length, the split fish set into it, little cross sticks "inserted in a crosswise position in order to keep the fish flat so that the heat could get at the whole piece", and the long stick driven into the ground at a slant with the fire built under it. So the honest credit is this: fire-roasting split salmon on cedar and other wood, at an open fire, is Chinookan and Coast Salish practice, and it is centuries older than any restaurant menu. But in both of these accounts the wood holds the fish up beside the fire; it does not lie under it. In the same Puget Sound monograph the cedar plank is the building board — houses a hundred to two hundred feet long "were built of cedar planks which were split from the tree trunks with wedges of elk horn". A plank on a gas grill with the lid down is a modern object that borrows a very old idea, and it is worth saying which is which.
The plan for this article pointed at the Far West files of America Eats, the Federal Writers' Project food survey. Its archive answers 503 on every path as of 23 September 2026, so nothing here is attributed to it. What is open is the fishery. John N. Cobb's Pacific Salmon Fisheries, Bureau of Fisheries Document No. 1092, printed as Appendix XIII to the Report of the Commissioner of Fisheries for 1930, sorts the runs species by species: the chinook or king is "the largest of the Pacific salmons", with "an average weight of about 22 pounds, but individuals weighing 70 to over 100 pounds are occasionally taken", and — the line that governs when you can cook this — "In Puget Sound chinook salmon are found throughout the year, although it is only during the spawning season that they are very abundant." Who catches them is federal court record and not folklore. Article V of the Treaty of Point Elliott, 12 Stat. 927, signed in 1855, secured the right of taking fish at usual and accustomed grounds and stations to the signatory tribes "in common with all citizens of the territory". In February 1974, in United States v. Washington, 384 F. Supp. 312, the district court for Western Washington read that phrase as guaranteeing the treaty tribes the "opportunity to take up to 50% of the harvestable number of fish", and the Ninth Circuit affirmed at 520 F.2d 676 in 1975. Half of the salmon on a Washington counter comes ashore under that holding. A recipe is not the place to argue it, but it is the place to know it.
Why this version works
Species is not a garnish. USDA FoodData Central puts raw chinook at 10.4 g of fat per 100 g, against 4.69 g for sockeye and 4.4 g for pink. King has more than twice the fat of the other two, and that fat is the entire margin for error on a hot board. Sockeye is leaner, firmer and darker and wants to come off around 115°F. Pink, at an average of about four pounds a fish, is a thin fillet that will be over before you have opened the lid, and it is better canned or in a cake than on a plank.
Salt first, then dry the surface. A tablespoon of salt left on the fish for half an hour pulls water out of the outer few millimeters and then goes back in with it, seasoning the flesh rather than the plate and firming the outer layer so it does not shred. Wiping it dry and leaving it uncovered for twenty minutes more gives you a tacky surface — a pellicle, the same thing a smokehouse builds — and smoke sticks to that surface and slides off a wet one.
Take it off at 120°F, not at 145°F. The FDA Food Code 2022, §3-401.11(A)(1), calls for 63°C (145°F) held for 15 seconds for fish. That is a model code written for restaurants and retail, where the cook does not know the customer; it is the safety floor, and if anyone at your table is pregnant, elderly, very young or immune-compromised, cook to it. For an intact fillet from a fishmonger, cooked at home for healthy adults, 145°F in the center is a fish whose fat has already been squeezed out onto the board. Pull a king at 120°F in the thickest part and let carryover bring it to about 125°F while it rests.
The plank is a heat buffer before it is a smoke source. A soaked board between the fire and the fish means the underside never meets metal or radiant coal heat. The water in the wood boils off first, so for the first several minutes the fillet is being steamed from below at a little over 212°F while the trapped air under the lid does the rest. Only once the surface of the board dries out and starts to char does it give smoke, which is late in the cook and is exactly when you want it — a short, resinous hit rather than a long one.