Hurries to the river grasses (6)
I believe the answer is:
rushes
'hurries to the river grasses' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for rushes that I've seen before include "Charges too much" , "Moves quickly" , "Grasslike plants in wet places" , "Wetland plants" , "first prints" .)