Identification of herbivore coprolites are tough. First of all, they are very rare. Secondly, vegetable matter is not always visible on the surface. The shape of this specimen reminds me a bit of the droppings left by the Canadian geese that frequent my part of the world. Could this be a dropping of a duckbill dinosaur? It was found among other possible coprolites in a 100' x 100' area near a nesting site where egg shells and the remains of baby Maiasaura were found.