This was a type of treasure known as 'Saber Intent Condensing Grass' that True Monarch White Crane gave to Song Shuhang in exchange for his demodragon medicine. This type of treasure grew in the ruins of Immortals that have comprehended the principles of the saber, and it was something very useful for cultivators that used the saber.
After eating these blades of grass, they would have the opportunity to experience and comprehend 'saber intent'.
If one had enough of these blades of 'Saber Intent Condensing Grass', they would be able to condense 'saber intent' just by eating them as long as their talent wasn't too bad.
Song Shuhang saw Su Clan's Sixteen and smiled, saying, "Sixteen, did you also eat this 'Saber Intent Condensing Grass'?"
