Here's why:
* Dry: Chaparrals are characterized by their arid climate with hot, dry summers and mild, wet winters.
* Scrubland: The vegetation is dominated by shrubs, small trees, and grasses.
* Dense: The vegetation is often thick and closely spaced.
* Low-lying: The plants are typically short and close to the ground.
While other phrases might describe aspects of a chaparral, they don't capture the full essence like this one does.