The induku was a type of plant lifeform from the planet Vulcan, a type of tree with flame-colored leaves. Like most plant life on Vulcan, the Induku tree was adapted to the hot, dry climate there, growing near oases in the desert.
In 2253, Spock thought of the induku tree when noticing the lush plant life collected in the parklands of Ka'a Beach on Kauai, Hawaii, on Earth. He found it interesting how the water-rich environment allowed for a wide diversity of plants so different from those on his homeworld. (TOS novel: Vulcan's Glory)