Due to variation in altitude, aspect and soil, a diversity of vegetation is discernible in the protected area. The vegetation of the Overa-Aru Wildlife Sanctuary is mainly Fir (Abis pindrow) with Kail (Pinus griffithi) in the lower elevations near Nallas. On varied physical variations the following forest types found are as:

Riverian Vegetation

1600-2300m ASL

The most dominating tree species of the area is Kail (Pinus griffithi). The other species in association with this includes the broad leaved species of Aesculus indica, Fraxinus hookeri, Parrotiopsis jacqumentiana, Juglanos regia dotted Kail is also interspersed towards the upper limits and on ill drained sites. The constituent of the underside include Indogofera heterantha, Lonicera species, Vibernum, Skimmia laurel, Jasminium species etc.

Coniferous Forests

2200-3300 m ASL

Fir (Abies pindrow) is the dominating species of this area and is also found in association with Spruce (Picea smithiana) at 2300m. Fir (Abies pindrow) gives way to Abies spectables in higher elevations. Kail (Pinus griffithi) is found mix on exposed slopes whereas along the upper trees Birch (Betula utilis) occurs along the upper reaches (at Lidderwath). The woodland also occupies some sides of different nallahs.

Alpine Scrubs and Pastures

Beyond 3400m ASL

This type of forests contains mostly of treeless pastures having scattered scrub vegetation. This area is mostly dominated by Birch (Betula utilis) near the tree line at Lidderwath Kolhai. The area is also supported by Juniperous recura, Rhododeindron species, Viburnum species, Lonicera species at different places with Primula at shady places.

The extensive alpine pastures above the tree line bear a luxuriant growth of perennial herbs and grasses. They are known as ‘Margs’. The distribution of these pasture land is in upper reaches of Sikiwas, Lidderwath and in upper reaches of Chummnaii and Kolhaie. The dominated shrub species are Myostotis species, Cynoglossum compounalutun species and Betuala utilis are found dotted at some places.

Checklist Of Medicinal Plants Present In Overa Aru Wildlife Sanctuary