Pinnacles National Park has some of the largest gray pines I've seen.
GRAY PINE grows only in California, encircling the central valley nearly entirely at around 1,000 feet to 3,000 feet. It often associates with blue oak (Quercus douglasii) in the hot, dry foothills, and grows in open woodlands just below the ponderosa pine belt. It is also called foothill pine and ghost pine, and was formerly called digger pine. Gray pine is drought tolerant, and can survive on 10 inches of annual rainfall. More interesting details are found in this blog post.
Gray pine is an open, sparsely foliaged pine, usually multi-trunked, and not particularly large, but can grow to 100 feet. Reports from earlier times mention that gray pine could be up to 140 feet high and 3 to 12 feet in diameter, and may have lived over 200 years.
On a cycling trip in Big Sur I was surprised to find a few gray pines growing uncharacteristically almost to the Pacific Ocean.
The American Conifer Society has a wonderful, descriptive page about gray pine here.
Thick 8 to 12 inch grayish-green needles hang loosely and occur in groups of three.
The heavy cones are 6 to 10 inches long, with sharp pointed scales, and take two years to mature. The seeds are large and nutritious. These cones are second in mass only to Coulter pine (Pinus coulteri).