A person under sixteen years of age shall not operate a snowmobile on a designated snowmobile trail, public land, or public ice unless the operation is under the direct supervision of a parent, legal guardian, or another person of at least eighteen years of age authorized by the parent or guardian, who is experienced in snowmobile operation and who possesses a valid driver’s license, as defined in section 321.1 , or an education certificate issued under this chapter . [C73, 75, 77, 79, 81, §321G.20 ] 89 Acts, ch 244, §32 ; 90 Acts, ch 1230, §81 ; 98 Acts, ch 1073, §9 ; 2004 Acts, ch 1132, §29 ; 2012 Acts, ch 1100, §21 ; 2013 Acts, ch 90, §85 ; 2014 Acts, ch 1141, §56 Referred to in §805.8B(2)(g) For applicable scheduled fine, see §805.8B , subsection 2, paragraph g