If said district, before the division was made, was under the control and management of trustees, then each trustee shall continue to serve in the district in which the trustee is situated, and other trustees shall be elected in each new district. The election for said new trustees shall be called by the old board of trustees in each district within ten days after said division is made and shall be conducted as provided for the election of trustees.
Iowa Code § 468.365
89 Acts, ch 126, §2
Election of trustees and management of districts, subchapter III