Broadshare

This plough possesses the recommendations of being a Broadshare, Scarifier, and Subsoil Plough, combined in one and the same implement.

Source: wiktionary

Immediately after the broadshare, the harrow is twice used to free the ground from the stubble, which is gathered in rows every fifteen or twenty rods, according to quantity, and if thought worth the labor, or in default of straw enough, this is carried to the yards, to be trodden into manure; otherwise it is burnt.

Source: wiktionary

The surface is first broken with a cultivator fitted with broad blades, a plough, or a broadshare.

Source: wiktionary

When land proves to be very foul after harvest, it is best, first to shallow, spuddle, or broadshare the surface, harrow up the weeds, cart them to a mixen, or burn them on the spot:

Source: wiktionary