Notwithstanding any provision of this chapter to the contrary, this chapter shall not exempt from the ad valorem tax nor subject to the excise tax imposed by this chapter, Christmas trees and short-rotation hardwoods, which are cultivated by agricultural methods, and the land on which the Christmas trees and short-rotation hardwoods stand shall not be taxed as provided in RCW
84.33.140. However, short-rotation hardwoods, which are cultivated by agricultural methods, on land classified as timberland under chapter
84.34 RCW, shall be subject to the excise tax imposed under this chapter.