David McHattie Forbes (21 July 1863 – 23 March 1937) was a Scottish botanist, ethnologist, sugarcane plantation manager and explorer on the island of Hawai'i.

He practised forestry, agronomy, and horticulture and served as the first district forester of South Kohala in 1905, and twenty years later was appointed a judge in Waimea.

The location of the find became known as Forbes Cave and his family preserved his third of the found objects for half a century until they donated them to the Volcanoes National Park in 1956.

[citation needed] In 1887, at the behest of William H. Purvis, David Forbes travelled to Kukuihaele near Waipio Valley, Hawaii, via Cape Horn, to manage an experiment in cinchona cultivation above the sugar line.

Purvis, who had already introduced the macadamia nut from Australia, recognised the potential benefits of finding a species of tree that would thrive in the land above the sugarcane, above 1500 feet, called the sugar line.

Next to Forbes, visitors will find such names as Amelia Earhart, Babe Ruth, and Franklin Delano Roosevelt on plaques affixed to the trees.