Scorched earth
A scorched-earth policy is a military strategy that aims to destroy anything that might be useful to the enemy while it is advancing through or withdrawing from a location. Any assets that could be used by the enemy may be targeted, for example food sources, water supplies, transportation, communications, industrial resources, and even the locale's people themselves.
Coastal defence of colonial Chile
When the Spanish learned about the impeding Dutch expedition to Valdivia in the 1640s Pedro de Toledo, Viceroy of Peru, sent letters ordering local Spanish authorieties use a scorched earth strategy against the invaders.