Mich. Comp. Laws § 252.2

Sec. 2. The term “super-highway” shall include any highway of a width ranging from 120 to 204 feet or more and in special instances of a width of not less than 106 feet and when established shall be deemed a public highway. The term “limited access highway” shall include such highways as are especially designed for through traffic, and over, from or to which owners or occupants of abutting land have no easement or right of light, air or access by reason of such abuttal. Super-highways or limited access highways may be parkways, with or without landscaped roadsides, from which trucks, buses and other commercial vehicles may be excluded; or they may be motorways open to use by all common forms of highway traffic.