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.
Roman infantry tactics
The systematic wastage and destruction of enemy economic and human resources was called "vastatio" by the Romans. Crops and animals were destroyed or carried off, and local populaces were massacred or enslaved. Sometimes these tactics were also used to conduct punitive raids on barbarian tribes which had performed raids across the border. In the campaigns of Germanicus, Roman troops in the combat area carried out a "scorched earth" approach against their Germanic foes, devastating the land they depended on for supplies. ""The country was wasted by fire and sword fifty miles round; nor sex nor age found mercy; places sacred and profane had the equal lot of destruction, all razed to the ground.."" (Tacitus, "Annals"). The Roman "grind down" approach is also seen in the Bar Kokba Jewish revolt against the Romans. The Roman commander Severus avoided meeting the hard-fighting Jewish rebels in the open field. Instead he relied on attacking their fortified strongpoints and devastating the zone of conflict in a methodical campaign. This "attritional" aspect of the Roman approach to combat contrasts with the notion of brilliant generalship or tactics sometimes seen in popular depictions of the Roman infantry.