Salting the earth
Salting the earth refers to the practice of spreading salt on fields to make them incapable of being used for crop-growing. This was done in ancient times at the end of some wars as an extremely punitive scorched earth tactic.
The most famous example of salting the earth supposedly occurred at the end of the Third Punic War in 146 BC between the Roman Republic and Carthage. After sacking the city of Carthage and forcing the few survivors into slavery, an area 50 miles around the city was reportedly salted. It is an open issue as to whether this event actually occurred. Aside from the logistics involved (it would have required a tremendous amount of salt, at the time so valuable that it was sometimes used as money) the first reference to the event is found in the Middle Ages, thus making it possible that the story was a later fabrication.
It does seem fairly certain however, that despite the expense and the logistics, salting the earth was indeed put into practice by the Romans' predecessors, the Assyrians. According to ancient records, they did this as a last resort, to capitals of neighboring countries who repeatedly rebelled against paying them tribute – including Mitanni in c. 1290 BC, and centuries later, Elam in c. 640 BC.
In Spain and the Spanish Empire, salt was poured into the land owned by a convicted traitor (often one who was executed and his head placed on a picota, or pike, afterwards) after his house was demolished. The practice was abandoned in the 17th century.
Likewise, in Portugal, salt was poured into the land owned by a convicted traitor. The last known event of this sort was the destruction of the Duke of Aveiro's palace in Lisbon in 1759, due to his participation in the Távora affair (a conspiracy against King Joseph I of Portugal). Demolished and salted, the palace's grounds gave place to a stone memorial in order to perpetuate the memory of the shame of the Aveiro House, where it is written (English translation): In this place were put to the ground and salted the houses of José Mascarenhas, stripped of the honours of Duque de Aveiro and others, convicted by sentence proclaimed in the Supreme Court of Inconfidences on the 12th of January 1759. Put to Justice as one of the leaders of the most barbarious and execrable upheavel that, on the night of the 3rd of September 1758, was committed against the most royal and sacred person of the Lord Joseph I. In this infamous land nothing may be built for all time.
The Red Army also salted Soviet fields as a part of the scorched earth policy against the Nazi invasion[citation needed]. It was reported that when the Soviets reclaimed the territory, they were equally unable to use it.[citation needed]
Today the term is used in a variety of ways, referring in general to any sort of poisoning. This varies from the direct in the use of area denial weapons or radiological weapons, to the philosophical, where it is often used to describe business strategy to avoid takeovers (similar to but broader in scope than a poison pill).
Vandals sometimes vandalize property by dumping salt into vegetation areas, eventually killing the plants.[citation needed]