Street trees shall be classified in accordance with the three (3) species size classes listed in the Blackfoot approved tree list. Street trees shall not be planted closer together than the following: small trees, twenty feet (20'); medium trees, thirty feet (30'); large trees, forty feet (40'). No trees may be planted closer to the back side of any curb or the nearest edge of any sidewalk than the following: small trees, two feet (2'); medium trees, four feet (4'); and large trees, six feet (6'). All distances shall be measured from the center of the tree trunk at ground level. (Ord. 2137, 10-6-2015, eff. 10-6-2015)