A petition to establish, modify the boundaries, or dissolve a county rail district shall be filed with the county legislative authority. The petition shall be signed by the owners of property valued at not less than seventy-five percent according to the assessed valuation for general taxation of the property for which establishment, modification or dissolution is petitioned. The petition shall set forth a legal description of the property and shall be accompanied by a plat which outlines the boundaries of the property sought to be annexed.