Cal. Food & Agric. Code § 6254

The assessment authorized to be assessed and levied is hereby declared to be in the nature of a special assessment, and the Legislature hereby finds that the owners of all winegrape plants will be benefited by the district to the same extent and in the same manner regardless of the age of the plants. The assessments authorized by this article to be assessed and levied shall be assessed and levied regardless of the age of the plants growing on the land.