More than a century ago, a Big Island sugar plantation manager introduced macadamia nuts to the island. Although native to the Australian rainforests, mac nuts thrived in Hawaii, and the state became the site of the world’s first commercial plantations. Today these delicious, hard-shelled nuts, which are high in the “good” fat that helps reduce cholesterol levels, are one of the Big Island’s largest crops.

Some 60 million pounds of mac nuts were produced on the Big Island in 2005/2006. With the exception of a small farm on Molokai, all the state’s mac nuts are grown on the Big Island.

Macadamia nuts are not picked from the tree. They fall to the ground fully ripened. Don’t pick one up expecting to shell it and pop it in your mouth. It requires 300 pounds of pressure per square inch to crack a mac nut shell. (Hint: To avoid smashing body parts, try wrapping the nut in an old sock or newspaper before hitting it with a hammer.) Commercially, the job gets done with high tech cracking machines, after which the nuts are roasted.

Mauna Loa Macadamia Nut Corp., six miles south of Hilo on Macadamia Road, and Hamakua Macadamia Nut Co., on Maluokalani Street in Kawaihae, welcome visits from people who want to know more about mac nut processing. At Mauna Loa, you’ll find a 2,500-acre orchard, a nut processing plant and chocolate factory. Hamakua offers a visitor center, self-guided tours and free samples.

For more information, pick up the “Great Hawaiian Mac Nut Trail,” a self-guided tour of the Big Island’s macadamia nut industry. You’ll find everything from processing plants to small family-owned farms and a bed-and-breakfast stop where visitors can pick mac nuts.