In Hindu rituals, the durva grass plays an important role. Rings made of the grass are often worn before starting either the ritual of homa — offerings to fire — and puja. The grass is believed to have a purifying effect on participants. Grass is also used as an offering in Ganesha temples.
To know more about "Significance of Kusha/Durba grass" listen to 'What Is The Logic' with Dr. Sheesham Aggarwal now available on all audio platforms.
To know more about Upnishad read the book- https://www.amazon.in/s?i=stripbooks&rh=p_27%3ADr.+Shisham+Bansal&ref=dp_byline_sr_book_1