Whenever in any cemetery or place of burial of human remains, which is established or organized under the authority of the board of supervisors of any county or the governing body of any city, there is any known grave of a former soldier, sailor, or marine of the United States who was not dishonorably discharged from the service, the officers who manage such cemetery or place of burial shall keep such grave properly marked and identified, and free from weeds and rubbish, and keep in decent order and repair and free from defacement, injury, and unlawful markings any tomb, monument, gravestone, wall, or other appurtenance to such grave.