A briar patch is a common name for a thicket of thorny plants.

The Briar Patch is named after its similarities. (TNG movie: Insurrection)

While the USS Enterprise-D was evading Borg cubes inside of a nebula in an alternate timeline, Captain Jean-Luc Picard likened their tactics to trying to flush a rabbit out of a briar patch. (Star Trek novel: Engines of Destiny)