Why can't we harvest Leymus chinensis in rainy days?

The reason why Leymus chinensis can't be harvested in rainy days is that increasing the water content of Leymus chinensis in rainy days is not conducive to storage. Leymus chinensis is mainly used for mowing or grazing, and should be harvested in sunny weather. After cutting and drying for one day, it can be folded into straw strips manually or mechanically, and then slowly dried in the shade, and the straw strips can be connected into a large pile, so that the water content can be reduced to about 15% before storage.