The smell of freshly cut grass/hay is perfectly normal after harvest. Is goes away during the drying/curing process as long as the processed isnt rushed. I made that mistake my first grow, and to a lesser extent, during my second grow too lol. Most growers seem to have their own way of curing that suites them. For me personaly, I found that hanging them for a period of 5-7 days and then jaring them to cure. Once jarred I burp them on occasion at the bigining and then burp them less and less as the days and weeks pass by. Usually the smell of wet cut grass begins to go away after a couple/few weeks depending of course on temps, strain and size/age of plants. In my experience, all the mistakes I made in the curing process were because I didnt dry them enough before curing and because of that they never seemed to get that nice smell/taste. But I eventualy learned the hardway lol. As I say, lots of people have their own methods of drying/curing, but the most important thing in my limited experience is not to rush it.