The forest cover in the Sanjay Gandhi National Park is chiefly of the South Indian moist deciduous and Semi Evergreen types including the moist teak-bearing forest, mangrove scrub, southern moist mixed deciduous forest, and western subtropical hill forest.
Major trees of this area include Adina Cordifolia (Kadamb), Albizia lebek (Shirish), Pongamia pianata (Karanj), Tectona grandis (Teak), Dalbergia latifolia (Sesum), species of Acacia, Zizyphus, Euphorbia, Butea monosperma (Flame of the Forest), Bombax malbaricum (Red silk cotton), Vad, Peepal, Umbar, Neem and Erytherina indica (Indian coral tree). The abundance of woody climbers (Liana) stands testimony to a more humid past. Other notable species here are abundant bamboo, orchids, Zingiberaceae Species, Costus Species, and the seven yearly mass flowering of Strobilanthes Species (Karvi).
Rich mangroves line the Thane Bassein creek that passes right through the park. Lichens, fungi, ferns, mushrooms, medicinal herbs and a multitude of other kinds of flora abound here, and this forest is well known for the existence of many endangered species and rare life forms.
The thick forest cover of the park naturally renders an invaluable service of helping lower pollution levels in the city by supplying fresh oxygen and acting as a sink. By serving as a huge natural generator of life-sustaining oxygen, the National Park meets the need of the habitants of the region, more specifically, the twin cities of Thane and Mumbai.
The forest cover also constitutes an excellent catchment area for the Tulsi and Vihar lakes.
Many a small thing has been made large by the right kind of advertising.
-- Mark Twain (1835 - 1910), A Connecticult Yankee in King Arthur's Court