Section 188-29-05 - Harvesting Restrictions for RockweedA. The seaweed Ascophyllum nodosum, also known as rockweed, must be harvested according to the following criteria: (1) the lowest lateral branches shall remain undisturbed and attached to the main stalk of the rockweed that is attached to the substrate; and(2) a minimum of 16 inches of the rockweed shall remain above the holdfast.13- 188 C.M.R. ch. 29, § 05