SHOCK n.
A pile or assemblage of sheaves of grain, as wheat, rye, or the like, set up in a field, the sheaves varying in number from twelve to sixteen; a stook. And cause it on shocks to be by and by set. Tusser. Behind the master walks, builds up the shocks. Thomson.
STACK a. 5 definitions
A large pile of hay, grain, straw, or the like, usually of a nearly conical form, but sometimes rectangular or oblong, contracted at the top to a point or ridge, and sometimes covered with thatch. But corn was housed, and beans were in the stack. Cowper.