[Washington · personal use]
Washington: licensed, 10 pounds a day, and almost never in a state park.
A WDFW fishing license covers seaweed. The daily limit is 10 pounds wet weight, cut with a knife or scissors, holdfast left on the rock. The beaches most people assume are open — state parks — are the ones that are closed.
I keep this current because I use it myself, but agencies change rules mid-season. The official links above win every time.
License
Any Washington fishing license that includes shellfish/seaweed covers you. Buy it online through WDFW before you go — there is no on-beach option.
Daily limit
10 pounds wet weight per person per day, all species combined. Weigh it once, at the beach, before you leave.
Where it is closed
Washington State Parks are closed to seaweed harvest year-round, with one exception: Fort Ebey, Fort Flagler, and Fort Worden, April 16 to May 15 only.
Cutting rules
Knife or scissors only — never rakes or tined forks, never tearing from the rock. Bull kelp (Nereocystis) is cut no closer than 24 inches above the bulb; short-stemmed kelps like sugar kelp (Saccharina) and winged kelp (Alaria) no closer than 12 inches above the holdfast. The holdfast stays attached, where you found it.
Private tidelands
A huge share of Puget Sound beach is privately owned below the high-tide line. You need the owner permission, license or not. If ownership is not verifiable, I mark the site unverified rather than guess.
No sale, no barter
Commercial harvest is prohibited for personal license holders on both public and private tidelands. Take only what you will actually cook.
Discover Pass
Required for the parking lot at any Washington State Park ($10/day or $30/year), separate from your fishing license. Everyone needs it — harvesting or not.
Before you cook
Rinse in warm fresh water. Never harvest near an outfall, marina, industrial site, or an active DOH closure — and check the DOH biotoxin map the morning you go.