Ala. Code § 16-48-5

The trustees of the institute other than the Governor and State Superintendent of Education are divided into three classes, as follows: The trustees from the Fourth, Fifth and Seventh districts shall constitute the first class; those from the Second, Sixth and Eighth Districts shall constitute the second class; and those from the First, Third and Ninth Districts shall constitute the third class; and they shall hold office and their seats shall be vacated as prescribed by Section 266 of the constitution.