Traditionally seaweed is harvested by hand. Flat-bottomed rowboats are used to maneuver among the beds so the beds are not disturbed and so the boats don't run aground on the rocks, among which most macroalgae, or seaweed, grows. Other popular seaweed grows up directly from the bottom of the ocean, is independent of any land-based nutrients and is perpetually submerged in the ocean's salt water. However, it is the rock-based seaweed that is most often harvested by hand. Coastal states and municipalities legislate the harvest of seaweed, or macroalgae, to promote sustainable development and guard against over harvest and damage to the wild growing beds.
Research all state laws and regulations and all local ordinances pertaining to the harvest of seaweed. State laws are available through a state legislature's website and most local ordinances are searchable via Municode.com. The harvest of seaweed falls under state departments of fisheries, and these state departments usually have their own websites, linked off the executive branch of state government, where departmental regulations are available. Incorporate any requirements mandated by state or local law into the procedure for harvesting.
Research the stretch of seashore in which you plan to harvest seaweed and choose a specific place with the clearest water and cleanest beaches. Steer clear of heavily traveled areas, as pollution from recreational boats and boaters contaminates the water, sea floor and ultimately the seaweed. Also look for an area for harvesting that is protected from the worst of the waves and presents some protection in the form of lagoons and alcoves, or lines of rock formations.
Pick an overcast day to harvest the seaweed, as harsh sun is hard on both the harvester and the harvested seaweed, causing it to dry out too quickly even when well-iced coolers are waiting for it on the boat.
Borrow, rent or purchase a flat-bottomed boat with oars for propulsion and row it into the selected rocky area intended for the harvest of the seaweed. Anchor the boat with a traditional anchor or with a weighted rope so the boat won't drift or be battered against the rocks.
Wade or swim to the first rock where seaweed is attached and use sterile stainless steel scissors to cut the seaweed leaves, being careful to leave the holdfast, or the seaweed plant roots, untouched and undamaged, as the plants will grow back from the holdfasts.
Place the leaves in a mesh drawstring bag and allow the bag to drag in the water to keep the seaweed wet and cool as harvesting continues.
Return to the boat at least every ten minutes to empty the drawstring bag into an ice chest filled with seawater and ice to keep the seaweed fresh.
Repeat steps five through seven until seaweed is harvested in an amount reasonably expected to be immediately usable.