Clever Battle Tactics

Mar 2007
Circa 530, the Thuringians dug holes in the ground in front of their shield wall and covered the holes with turf so the holes looked like solid ground. When the Frankish cavalry charged their horses stepped onto the turf, fell through, and the charge was broken, with many horses breaking their legs, I'd imagine. It was only a temporary setback as the Franks later won the day.
Lot of interesting stories here.

The one you mention above, is very similar to the next section in Herodotus (8.28) that I quoted at the top. One of the other tactics the Phocians employed against the Thessalians was to dig a trench across the field, filled it with broken pottery jugs, then covered it with grass. Had a similar effect on the Thessalian cavalry as the Franks.