Iowa Code
Chapter 39 - ELECTIONS, ELECTORS, APPOINTMENTS, TERMS, AND OFFICERS
Section 39.18 - Board of supervisors.

39.18 Board of supervisors.
There shall be elected biennially in counties, members of the board of supervisors to succeed those whose terms of office will expire on the first day of January following the election which is not a Sunday or legal holiday. The term of office of each supervisor shall be four years, except as otherwise provided by section 331.208 or 331.209.
[C51, §239; R60, §475; C73, §295, 591; C97, §411, 1074; S13, §1074; SS15, §411; C24, 27, 31, 35, 39, §521; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, S81, §39.18; 81 Acts, ch 117, §1202]
87 Acts, ch 68, §1