Cal. FAC § 6981

(a) An annual assessment of 1 percent shall be levied on the gross sales of all deciduous pome and stone fruit trees, nut trees, olive trees, and grapevines, including seeds, seedlings, rootstocks, and topstock, including ornamental varieties of apple, apricot, crabapple, cherry, nectarine, olive, peach, pear, and plum, produced and sold within the state or produced within and shipped from the state by any licensed nursery dealer. For packaged or containerized stock, the assessment shall be levied on the producer’s bareroot price of the plants.

(b) The secretary, as appropriate, and on the recommendation of the board established pursuant to Section 6988, may exempt from the assessment certain species of pome and stone fruit, nut trees, grapevines, or varieties of olive trees, or ornamental varieties of apple, apricot, crabapple, cherry, nectarine, olive, peach, pear, and plum if it can be demonstrated that no benefit is derived by these species or varieties from programs described in subdivision (d).

(c) The assessment shall be applied at the point of sale where the nursery stock is sold by a producer to persons other than California producers of nursery stock that is subject to assessment under subdivision (a).

(d) The secretary may set the assessment at a lower percent to cover the costs necessary to implement and carry out all department programs established pursuant to Article 7 (commencing with Section 5821) of Chapter 8 of Part 1 concerning the registration and certification of pome and stone fruit trees, nut trees, olive trees, and grapevines; the University of California foundation plant materials service activities concerning pome and stone fruit trees, nut trees, olive trees, and grapevines; and other activities related to the development of planting materials for pome and stone fruit trees, nut trees, olive trees, and grapevines.