It's not all about the beach on Kauai
The monastery was founded in 1970 by Robert Hansen, a native of Oakland who danced with the San Francisco Ballet before his conversion to Hinduism. The monks have taken vows of poverty and engage in daily meditation; they tend the gardens, grow much of their own food and keep a small herd of dairy cows.

They are also decidedly tech-savvy. Wearing their hand-woven cotton robes, they sit at their Macs, publishing a quarterly journal, Hinduism Today (digital version available) and maintaining websites, including http://www.gurudeva.org. They have iPhones, they tweet and they blog.

Visitors coming by car must make reservations for the guided tours, which take place about once a week. (Free, donations encouraged.) The monastery is open from 9 a.m. to noon daily; (888) 735-1619.

LIMAHULI

On the North Shore in a verdant valley in the shadow of Makana Mountain ("Bali Hai" in "South Pacific") is Limahuli Garden. The setting is spectacular, but this is not just a beautiful place. Here, conservationists are at work undoing damage to the ecosystem from grazing cattle, feral pigs, invasive plant species, insects and fungi for which native species are defenseless.

Visitors learn which plants and trees are indigenous (native to Hawaii and other places), which are native (having reached Hawaii without human involvement) and which are endemic, having evolved in Hawaii from indigenous species and native only to Hawaii. Native plants, our guide told us, came by "wind, wing and weather," the seeds washed ashore or carried by wind, tropical storms or migrant birds. Many of Limahuli's native plants, such as the white hibiscus, which is endemic to Kauai, are rare or endangered.

Some of the introduced species — the modern introductions — are a big part of the problem. These introductions began with the arrival of Capt. James Cook in the islands in 1778 and continued through the plantation era, from the mid-1800s to the mid-1900s. They are not to be confused with Polynesian introductions, which were brought in voyagers' canoes as early as 200 and, for the most part, are useful species that do not tend to grow uncontrolled.

My tour began at the little visitor center, which is painted Hanalei green. There, I borrowed a walking stick (umbrellas are also provided, but this day we got lucky) and met up with our small group's guide, Kawika Goodale. His degree is in biology, but he's eminently qualified to take visitors around the garden: He is a sixth-generation Kauai native, and the land that is now the garden was a gift to Kauai from his grandmother Juliet Rice Wichman.

The tour of this peaceful place begins at lava rock terraces constructed perhaps 700 years ago as an irrigation system for farming taro, the food staple of the early Hawaiians. (Think poi.) Canals diverted water from Limahuli stream, which flows for more than 3,000 feet down to the ocean. Goodale told us that the stream is home to five species of Hawaiian saltwater fish that have evolved into freshwater fish.

As we followed a narrow trail uphill, Goodale pointed out a papala kepau tree, which early Hawaiians used as a bird catcher. They would attach a piece of its fruit, together with a flower as bait, to a twig. Birds landing on the twig would become stuck long enough to lose a few feathers, which were used for making cloaks, helmets and standards. Farther along, Goodale pointed out "public enemy No. 1," the schefflera, or octopus tree, with its bright red branches — an aggressive Australian import that grows like a weed in this valley.

Conservation of rare and endangered tropical species is a priority for the National Tropical Botanical Garden, which was established in 1964; there are four in Hawaii and one in Florida. Here at Limahuli, work is carried on in an adjacent 985-acre preserve that's not open to the public.

We saw breadfruit, originally brought to Kauai in canoes by Polynesians for whom it was an all-purpose tree: They ate its fruit, caulked their canoes with its gummy sap and used its leaves as sandpaper for polishing the wood for bowls, canoes and surfboards. Another versatile Polynesian introduction growing in the garden is the ti plant, whose leaves were used in cooking, for making sandals and for thatching roofs.

And there is sugar cane, which also came in those canoes. From it came food, medicine and primitive toothbrushes and, our guide told us, its silvery tassels were scattered on hillsides to create a slippery surface for sledding Hawaiian-style.

We saw a kukui, or candlenut tree, that is the official state tree, although it's a Polynesian introduction. It has spread into Kauai's forests as rats have carried fallen nuts. Rats are a problem here — "Two rats, three years, 17 million rats," observed Goodale.

As we paused at a viewpoint and gazed at the ocean, we heard a bit of the legend of Pohaku-o-Kane, which is about a family of rocks — two brothers and a sister — that washed ashore at Kauai. Like most Hawaiian legends, it's a complicated tale, involving the older rock brother's arduous efforts to reach the mountain ridge. But there he stands today, a large rock perched in plain sight on the east side of the valley.

The garden is almost at the end of Kuhio Highway north at Haena and is open Tuesday through Saturday, with guided tours ($30) at 10 a.m. by reservation and self-guided tours ($15) from 9:30 a.m. to 4 p.m. Reservations can be made online (except for Saturday tours) at tours.ntbg.org or at (808) 826-1053.