(a) Except as provided in Section 83.5, “improvements” includes both of the following:
(1) All buildings, structures, fixtures, and fences erected on or affixed to the land.
(2) All fruit, nut-bearing, or ornamental trees and vines, not of natural growth, and not exempt from taxation, except date palms under eight years of age.
(b) This section shall go into effect on the date Chapter 4.5 (commencing with Section 83) goes into effect pursuant to subdivision (a) of Section 88.