See Unusual Limestone Spires and Knobs at California's Mono Lake Tufa State Natural Reserve

If you happened to catch episode 6 of the Discovery Channel's LIFE series, you already know that California's Mono Lake is unique in that it is home to literally trillions of alkali flies. Along with brine shrimp, these flies are food for gulls, grebes and many migratory birds. While the vast swarms of flies certainly catch visitors' attention (not by biting people, thank goodness, but by congregating in thick layers along the shoreline), the most compelling natural attraction of Mono Lake is its misshapen calcium-carbonate spires and knobs called "tufa towers" (pronounced too-fah).

Although it's a good idea to first stop at the Mono Basin Scenic Area Visitor Center for a map and to learn about the area, you won't find actual tufas there. The best place to see these weird lumps and humps up close is along a one-mile self-guided nature trail in the Mono Lake Tufa State Natural Reserve about 5 miles south of the Visitor Center. Informative signs along the trail describe the history of the lake and explain the strange-looking limestone formations.

The most common way a tufa forms at Mono Lake is when an underwater spring rich in calcium mixes with lake water that is rich in carbonates. As the calcium comes in contact with carbonates in the lake, a chemical reaction occurs resulting in calcium carbonate- common limestone. Over the course of decades to centuries, a tufa tower will grow. Tufa towers grow exclusively underwater. Knowing that, you might be wondering why you are able see hundreds of them along a dry hiking trail?

The tufas were not always visible-most of the spires were hidden below the lake's surface. But beginning in 1941, to meet the growing water demands of Los Angeles, most of the major creeks and rivers that had sustained Mono Lake for centuries were diverted. This caused the lake level to drop 45 feet and its waters to double in salinity! Of course the lake's drop completely changed the eco system and wildlife habitat, causing concerned citizens and the National Audubon Society to take legal action to stop this drastic drain. Finally, in 1994, the lake was legally "saved" from further damage, and everyone agreed to raise the lake level by redirecting less water to Los Angeles. Slowly but surely the lake level has been going up, but it will never again reach its pre-diversion level.

Photographers may want to time their visit to Mono Lake Tufa State Natural Reserve for early morning or evening when the light and shadows create the most dramatic images. But regardless when you come, bring a hat and water because there is no shade along the trail.

Directions to Mono Lake Tufa State Natural Reserve trailhead: From Highway 395, about 5 miles south of the town of Lee Vining, turn east on Highway 120 and drive 5 miles to the signed turnoff for the South Tufa Area/Mono Lake Tufa State Reserve. Turn left and proceed a mile on good gravel road to a parking area near the trailhead.