We have all seen a set of grass (better known as Durva) being offered to gods. Let me tell you a myth associated with it.
As per the myth, once Garuda (the eagle faced bird, also the carrier of Lord Vishnu) got some nectar from the moon for the Nagas (the serpent gods) as a price for releasing Garuda’s mother who was forcefully serving the serpents (why, is a different story). On seeing this, Indra tried to convince Garuda not to give it them, lest the Nagas become immortal.
Garuda was not agreeable to this as he had to get his mothers release, but suggested to Indra, that once he gave it to the Nagas, Indra could go and steal the nectar from them. Garuda placed the vessel on the grass and while the Nagas were bathing in the river, Indra stole the vessel.
The Nagas thinking that the nectar was on the grass, licked it, and the sharp spikes of the grass slit their tongues. Since then the serpents are said to have forked tongues and the grass which had touched the nectar is considered to be holy! That is the Durva grass.