The ard, ard plough, or scratch plough is a simple light plough without a mouldboard.In its simplest form it resembles a hoe, consisting of a draft-pole (either composite or a single piece) pierced with a nearly vertical, wooden, spiked head (or stock) which is dragged through the soil by draft animals and very rarely by people.

Rather than cutting and turning the soil to produce ridged furrows, the ard breaks up a narrow strip of soil and cuts a shallow furrow (or drill), leaving intervening strips undisturbed. The ard is not suited for clearing new land, so grass and undergrowth are usually removed with hoes or mattocks. Cross-ploughing is often necessary to break the soil up better.

Ards come in a number of varieties.Based on use, there are two kinds: the tilth ard, for cutting furrows in cleared land, and the rip ard, or sod buster, which has a hooked share that gouges deeper into the soil and more effectively clears virgin or fallow land. The two were in early times used in conjunction with each other. Third is the seed drill ard, used specifically in Mesopotamia, which added a funnel for dropping seed in the furrows as the ard cut them.

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