Nargu is one of the most densely populated protected areas of Himachal Pradesh, with human density above 100 per sq. km and livestock density 200 per sq. km. Interestingly, all legal procedures such as the final notification for declaration of a Sanctuary have been completed. Human beings have already occupied most of the flat areas and cultivable portions, leaving only inaccessible reaches for wildlife. Livestock graze all over the Sanctuary. Based on the classification of Champion and Seth (1968), six types of vegetation can be seen in this area: A small portion of Subalpine forest in the higher reaches, followed by Kharsu Oak Forest, Moist Temperate Deciduous Forest, Western Mixed Coniferous Forest, Moist Deodar Forest, Moru Oak Forest, Ban Oak Forest, and finally, Subtropical Pine Forest.
The Nargu Wildlife Sanctuary was established in 1962 and later re-notified in 1974. It is one of the most heavily inhabited nature reserves in Himachal Pradesh. There are several native Himalayan plants and animals that call the sanctuary their home.