I have been heavily researching this as im about to harvest.
So the hay smell is left over chlorophyll, and because you trimmed when wet (which is common) the plant couldnt break that down to sugars which metabolize into smells,odors,taste and even potency. Next time cut the plant down, with out removing any leaves whatsoever hang your entire plant upside down, approx 4 days later remove the biggest fan leaves, approx 4 days after that trim all the little resin covered sugar leaves close to the buds, then hang until stems snap, then you can start removing buds from branches and jar them and burp once every 12 hours for an hour for about 1 week then go to about once every 6 hours for 30 min, Real medical grade-A shit is slow dried, and by following these steps, your plants will break down left over chlorophyll into sugars, smells, odors, sweet tastes, and even more potent buds. Drying and curing is often done hastily and ruins all your hard work, by producing it into inferior product when it could have been shit so good it reeks through gasket sealed glass jars, tisk tisk, -shrug