In the trial of any action regarding title to a discontinued road or way, or portion thereof, brought pursuant to a decree under section 6654 or pursuant to sections 6655 to 6657, or of a counterclaim asserted pursuant to section 6654, the burden of proof concerning the construction of any deed or conveyance shall be borne by the party which is adverse to the party so owning said land immediately adjoining the discontinued road or way.   [PL 1971, c. 577 (NEW).]