Trees deemed significant for the purpose of this Chapter are those whose visual importance to the neighborhood is sufficient to justify special efforts to protect and preserve them and whose loss would be of irremediable adverse impact on the environment. Factors to be considered in determining the significance of trees are age, size, rarity and appearance. Notwithstanding the preceding, each of the following is declared to be a significant tree or trees:

A. Oaks or redwood trees having a circumference greater than twenty (20) inches measured at a height of four (4) feet above ground level.

B. Any tree having a circumference greater than twenty-five (25) inches measured at a height of four (4) feet above ground level.

C. Any three (3) or more trees proposed to be removed from any parcel of property within a twelve (12) month period.