who decided to use grass in parks and recreational fields instead of dirt and why?"?

Answer 1

Probably because you get dirt all over you and it stains your shoes and socks very easily. Grass is indicative of a natural environment and is relaxing to the eye and brain.

Each park district decides for themselves how to decorate or landscape.

People generally find it much more pleasant to look at grass than dirt.

Answer 2

would you rather walk around dirt, or green grass?

i'm thinking nature played a hand in it.

Answer 3

I don't know who decided it, but it's certainly more pleasant, and less painful to fall on.