A person may post his land to prohibit criminal trespass and physical activities by posting signs of durable material with any words describing the physical activity prohibited, such as “No Hunting or Trespassing”, printed with block letters no less than 2 inches in height, and with the name and address of the owner or lessee of such land. Such signs shall be posted not more than 100 yards apart on all sides and shall also be posted at gates, bars and commonly used entrances. This section shall not prevent any owner from adding to the language required by this section.