Cal. Food & Agric. Code § 52257

“Prohibited noxious weed seed” means the seed or propagule of any species of noxious weed which the director, as provided in Section 52332, finds and declares to be a prohibited noxious weed seed and which either: (1) is not known to occur, or is of limited distribution, in this state; (2) is not widely distributed throughout the state and which not only reproduce by seed, but also by underground roots or stems; or (3) is under eradication measures in this state.