On the basis of the salinity the Sundarban is divided into three zones:
Non-Saline Zone: Usually the area near the rivers, canals and channels are non-saline. Main plant of this area is Sundari (Heritiera fomes). Besides Geowa, Keora, Golpata, Amur, Hintal, Hargoja are also found to grow in abundance.
Mild Saline Zone: Main plant of this region is Geowa (Excoecarla agallocha) and among other plants there grow Pashur, Khapu, Kankra, Sada bain, Kala bain and Pakka Sundari.
Saline Zone: Major plants of this region are Garan, (Cerlops roxburghlana), Dhundal, Pashur, Kankra etc.