Summer is the season of tenacity, when tarweed and coyotes defy the Sun’s lethal stare. Bracketing California’s arid center are mountains and ocean: A surge of summer heat in the Sierra unleashes water from the snowpack, makes rivers run wild. Like a sorcerer the Pacific Ocean conjures up a marine layer thousands of feet tall; the fog drifts inland overnight in silence while we dream summer dreams.

Viewed from the battlements of Round Valley's Castle Ridge, marine fog swamps the peaks of Mt. Diablo.

Fog floods the spurs and draws of Mt. Tamalpais.

Tarweed, a summer survivalist, thrives in Round Valley's Murphy Meadow.

A coyote seeks sheltering shade along Round Valley's Arroyo Grande.

A plume of Pacific is launched at The Slot, Point Lobos State Reserve.

Mountain pride penstemon, Lake Tahoe.

Hiking buddy Mark soaks in the scenery at Sunol Regional Wilderness.

The Merced River below Vernal Fall, Yosemite National Park.

A gopher snake basks in morning sunlight at Mt. Diablo State Park.

Summer shadows on Mt. Diablo fall southwest at sunrise. Viewed from the Round Valley summit.

Elegant brodeaia, Morgan Territory Regional Preserve.

Boogie boarders prep for the next assault of surf at Stinson Beach.

A volt of turkey vultures scours the scenery for carrion at Round Valley.

Fog blankets San Pablo Bay between Mt. Diablo and Mt. Tamalpais.

East Bay Regional Park District workers start a "prescribed burn" in Round Valley's Murphy Meadow.

Salt heliotrope, Round Valley Creek.

Mt. Diablo's North Peak viewed from Morgan Territory's Highland Ridge on a windy morning.

A rider navigates the switchbacks leading to the crest of Round Valley's Hardy Canyon.

Dune buckwheat, Point Lobos State Reserve.

Coast live oak, Mt. Tamalpais.

A harvester combine, relic of the ranching era of former Round Valley owner Jim Murphy, sizzles in the summer Sun.

Pacific stonecrop atop Lembert Dome, Yosemite National Park.

A family frolics in the Pacific at Stinson Beach.

Sunrise viewed from Round Valley.

Los Vaqueros Reservoir.

Sunset over Stinson Beach.