On this day, the sacred grass Kush in Hinduism is uprooted and collected by adherents for religious functions, rituals, Karmakanda and Shraddha etc.

[1][2][3][4] On the auspicious day of Kushi Amavasya the adherents after taking sacred bath go for uprooting Kushas in farm fields.

Kush is very important for religious, Vedic rituals, devine and ancestral rites like Shraadha and Pitripaksha.

[5] The tradition of uprooting ‘Kusha’ is called Kushotpatan which has been practiced and followed for centuries in the Mithila region.

[1] And the mantra chanted during uprooting the Kusha is “om hoon phat phat swaha”[5] Similarly another mantra chanted during uprooting the Kusha is "viranchina sahotpanna parameshthinnisargaj, nud sarvani papani darbha swastikaro bhava"[7] After Bhadra Purnima this sacred Kusha is used in the oblations performed for the Vedic sage Agastya which marks the beginning of Pitrapaksha in Hinduism.