When any person owning or occupying land abutting on any highway has cut the brush and weeds on, removed the stones and rubbish from, and otherwise improved, the land within the limits of such highway between the traveled portion of such highway and such land, the selectmen of the town or other persons repairing such highway shall not place any stones, rubbish or waste material of any kind on the land so cleared and improved, and no other person shall place or leave any stones, rubbish or other waste material on such land. The provisions of this section shall not be construed to (1) prevent the selectmen or other legally authorized person or persons from making improvements upon any highway by widening such highway or reducing the grade thereof, or (2) authorize any improvements which conflict with the provisions of any ordinance adopted pursuant to § 7-149a. Any person violating any provision of this section shall be fined not more than ten dollars.