Michigan courts have applied a broad definition of what may serve as a boundary line for the purposes of acquiescence.
A line of trees, hedges, and some shrubbery was ruled a sufficient line to serve as an acquiesced boundary in Renwick v. Noggle, 247 Mich 150, 151-152; 225 NW 535 (1929).
A line of bushes was sufficient in Walters (After Remand), supra at 459.
In Sackett v. Atyeo, 217 Mich App 676, 682; 552 NW2d 536 (1996), the middle of a shared driveway was later declared to be an acquiesced boundary.
A rotted-away wooden fence represented by some steel fence posts and a driveway was deemed an acquiesced boundary in Geneja v. Ritter, 132 Mich App 206, 212-213; 347 NW2d 207 (1984).
In Siegel v. Renkiewicz Estate, 373 Mich 421, 425; 129 NW2d 876 (1964), the edge of a concrete sidewalk served as an acquiesced boundary.
Further, under the acquiescence theory, no parol transfer is required to permit the plaintiffs' predecessors' periods of possession to be tacked to establish the statutorily mandated period of fifteen years. Jackson v. Deemar, 373 Mich 22, 26; 127 NW2d 856 (1964); Siegel, supra at 425.