Wheat field bundles are called sheaves.
A bundle of wheat is called a sheaf. The plural is sheaves.
A shock.
a sheave is a pile of wheat or hay that is tied together with a cord or other kind of rope.
They gathered some sheaves from the corn to build the fire that celebrates the completion of the harvest. Pictures of wheat sheaves are a decorative motif that dates back many centuries.
Tying up bundles of freshly cut wheat or other grain.
A U.S. 1952 D wheat sheaves cent valued from 3 cents to 55 cents.
Grain is tied in sheaves.
The Sheaves of Wheat symbol is used to show prosperity and/or abundance. There are other less-common uses, but more than likely they're going for the prosperity approach.
Sheaves is the plural form of sheaf.
Stook or stack
Before crops were harvested by machines, many, especially cereals, were cut by hand using a scythe. After cutting, they were gathered into bunches - a good armful at a time, and tied - those bunches are sheaves. They were then stacked in small piles, usually called stooks, and left to dry completely before piling into very large stacks, called either stacks or ricks. During the winter, the wheat, oats, barley or whatever, was thrashed from the straw.