Poa pratensis, commonly known as Kentucky bluegrass, smooth meadow-grass, or common meadow-grass.
It is a perennial species of grass native to practically all of Europe, northern Asia and the mountains of Algeria and Morocco.
Although the species is spread over all of the cool, humid parts of the U.S., it is not native to North America.
Apparently the early colonists brought seed of Kentucky bluegrass to this country in mixtures with other grasses.
Poa pratensis forms a valuable pasture plant, characteristic of well-drained, fertile soil.
It is also used for making lawns in parks and gardens.
It is common in cool moist climates like the northeastern United States. (source)
So can chinchillas eat bluegrass?
Yes it is fine for them to eat, they will enjoy it very much.
For more foods that chinchillas can and can’t eat, check out our chinchilla food index