Sierra cement
n.β Β«The only vehicles allowed were gravel trucks and graders working to remove what is known as βSierra cement,β the type of thick, clumpy snow that can play havoc with tire treads and driversβ nerves.Β» ββMany Without Power Amid California Storm” by Jesse McKinley in San Francisco, California New York Times Jan. 6, 2008. (source: Double-Tongued Dictionary)