A threshing board, also known as threshing sledge,Columella, De Re Rustica (Book 1, chapter 6:23) is an obsolete agricultural implement used to separate cereals from their straw; that is, to thresh. It is a thick board, made with a variety of slats, with a shape between rectangular and trapezoidal, with the frontal part somewhat narrower and curved upward (like a sled or sledge) and whose bottom is covered with lithic flakes or razor-like metal blades.
One form, once common by the Mediterranean Sea, was "about three to four feet wide and six feet deep (these dimensions often vary, however), consisting of two or three wooden planks assembled to one another, of more than four inches wide, in which is several hard and cutting flints crammed into the bottom part pull along over the grains. In the rear part there is a large ring nailed, that is used to tie the rope that pulls it and to which two horses are usually harnessed; and a person, sitting on the threshing board, drives it in circles over the cereal that is spread on the threshing floor. Should the person need more weight, he need only put some big stones over it."
The dimensions of threshing boards varied. In Spain, they could be up to approximately two metres in length and a metre and a half wide. There were also smaller threshing boards, as little about a metre-and-a-half long and a metre wide. The thickness of the slats of the threshing board is some five or six cm. Nonetheless, since threshing boards are nowadays custom made, made to order or made smaller as an adornment or souvenir, they may range from miniatures up to the sizes previously described.
The threshing board has been traditionally pulled by mules or by oxen over the grains spread on the threshing floor. As it was moved in circles over the harvest that was spread, the stone chips or blades cut the straw and the ear of wheat (which remained between the threshing board and the pebbles on the ground), thus separating the seed without damaging it. The threshed grain was then gathered and set to be cleaned by some means of winnowing.
Traditional threshing systems
Until the arrival of combine harvesters, which reap, thresh and clean grain in a single process, the traditional methods of threshing cereals and some legumes were those described by Pliny the Elder in his Natural History, with three variants: "The cereals are threshed in some places with the threshing board on the threshing floor; in others they are trampled by a train of horses, and in others they are beaten with flails".«Messis ipsa alibi tribulis in area, alibi equarum gressibus exteritur, alibi perticis flagellatur» Gaius Plinius Secundus, Naturalis Historia, Liber XVIII (naturae frugum), lxxii - 298; Pliny the Elder, Natural History, Book XVIII (Agriculture), lxxii - 298.
In this manner, Pliny refers to the three traditional methods of threshing grain: Beating sheafs of grain against a crushing stone or lump of wood. Trampling grain spread on the threshing floor; the trampling would be done by a train of mules or oxen Threshing with flails, a type of traditional wooden tool with which one strikes the pile of grain until the seed is separated from the chaff.
Threshing with the threshing board The threshing board is a historical form of threshing that can still be seen in some regions that practice marginal agriculture. It is also somewhat preserved as an occasional folkloric and ceremonial practice, to commemorate traditional local customs. La trilla tradicional en Castroviejo, Rioja Alta ("Traditional threshing in Castroviejo, Rioja Alta, Spain").
For threshing with the threshing board, firstly one brings the baled stalks to the threshing floor. Some are stacked, waiting their turn, and others are untied and placed in a circle forming a pile of grain that is heated by the sun. Then farmers drag the threshing board over the stalks, first going several times around in circles, and then in figure-eights, and stirring the grain with a wooden pitchfork. Sometimes, this work was done with another kind of threshing implement: a Plostellum punicum (Latin; literally "Punic cart") or threshing cart, fitted with a group of rollers, each with metallic transverse razors. In this first stage, the straw is detached from the ear; much chaff and dirty dust remains, mixed with the edible grain. Every time the work of dragging the threshing board is repeated, the grain is stirred again, moving more straw to the edge of the threshing floor. If too much grain is spread on the ground, it has to be raked and swept in order to make a round mound and, if possible, to remove as much straw as possible.
After turning the grain and straw upside down and leaving it to dry during a meal break, farmers carry out a second round of threshing in order to separate the last of the grain from the straw. Then, they use pitchforks, rakes and brooms to create a mound. A pair of oxen or mules pulls the threshing board by means of a chain or a strap fixed to a hook nailed in the front plank; donkeys are not used, because unlike mules and oxen they often defecate on the crops. The driver rides on the threshing board, both guiding the draft animals and increasing the weight of the threshing board. If the driver's weight is not enough, large stones are put on the board. In recent times, the animals are sometimes replaced with a tractor; because the driver no longer sits on the board, the weight of stones becomes more important. Children enjoy riding on the threshing board for fun, and the farmers allow it because their weight is useful, as long as the children are not too boisterous. During this process, if the stalks are excessively squashed, two large metal arcs are affixed to the back of the threshing board; these turn-up and give volume to the straws, behind the threshing.
After threshing is finished, to avoid mixing the dirty remnants with the clean, new stalks, the threshing floor must be cleaned first with a rake to move the heavier material, and then with several brooms (in the narrow sense: they are typically made from "broom shrub"—Cytisus scoparius—and are stronger than domestic brooms). Also the straw was accumulated carefully and stored, because it was a good fodder for livestock. The entire process of threshing generates a thin dust that soaks in through the respiratory system and sticks to the throat.
During the sweeping, the husks and the chaff are separated to one part of the threshing-floor, while the grain, still not entirely clean, was winnowed, either by traditional of winnowing with sieves, or by a mechanical winnowing machine.
Traditional threshing implements (including the threshing board) were gradually abandoned and replaced by modern combine harvesters. This change, of course, occurred in some areas before others. For instance, in Spain, it happened in the 1950s and 1960s. Until that time, threshing boards were made in certain particular towns and villages with specialised craftsmen. Whereas the woodworking involved is simple, even rough, the flintknapping and the inlaying of flakes into the bottom of board need specialised skills that were passed from father to son. The most famous Spanish town for this work was, doubtlessly, Cantalejo (Segovia), where the craftsmen who made threshing boards were known as briqueros.
History
Origins in the Neolithic and Copper Age
Patricia C. Anderson (of Centre d’Etudes Préhistoire, Antiquité et Moyen Age del CNRS), discovered archaeological remains that demonstrate the existence of threshing boards at least 8,000 years old in the Near East and Balkans. The artefacts are lithic flakes and, above all obsidian or flint blades, recognizable through the type of microscopic wear that it has. Her work was completed by Jacques Chabot (of the Centre interuniversitaire d'études sur les lettres, les arts et les traditions, CELAT), who has studied Mitanni (northern Mesopotamia and Armenia). Both count among their specialties the study of microwear analysis, through which it is possible to take a particular piece of flint or obsidian (to take the most common examples) and determine the tasks for which it was used. Concretely, the cutting of cereals leaves a very characteristic glossy pattern of wear, owing to the presence of microscopic mineral particles (phytoliths) in the stalks of the plants. Therefore, scholars using controlled experimental replication studies and functional analysis with a scanning electron microscope are able to identify stone artefacts that were used as sickles or the teeth of threshing boards. The edge damage on the pieces used in threshing boards is distinct because, besides the glossy abrasion characteristic of cutting cereals, they have micro-scars from chipping, as a result of the blows of the threshing board against the rock surface of the threshing floor. (p. 222 and footnote 10)
The most productive archaeological site is Aratashen, Armenia: a village occupied between 5000 and 3000 BC (Neolithic and Copper Age). The archaeological excavations have provided thousands of pieces from the knapping of obsidian (suggesting that Aratashen was a centre of production and trade of artefacts of that highly regarded stone); the rest of the archaeological record consists mainly of fragments of common pottery, ground stones, and other agricultural tools. Analysing a sample of 200 lithic flakes and blades, selected from the best-preserved pieces, it is possible to differentiate between those used in sickles and those used in threshing boards. The lithic blades of obsidian were knapped using highly developed and standardized methods, such as the use of a "pectoral crutch" with a copper point. «Grande béquille pectorale»: Beginning at the headwaters of the river Euphrates, where this site is located, the craftsmen and peddlers sold their wares throughout the Middle East.
The threshing boards must have been important in the protohistory of Mesopotamia, since they already appear in some of the oldest written documents discovered: specifically, several sandstone tablets from the early town of Kish (Iraq), engraved with cuneiform pictograms, which could be the world's oldest surviving written record, dating to the middle of the 4th millennium BC (Early Uruk period). One of these tablets, preserved in the Ashmolean Museum of Oxford University, appears to have pictures of threshing boards on both faces, next to some numeric symbols and other pictograms. These presumed threshing boards (which might instead be sledges) have a shape similar to threshing carts that were used until recently in parts of the Middle East where non-industrial agriculture survived. Descriptions also appear in numerous cuneiform clay tablets as early as the third millennium BC.
There are another representation, in this case without writing, in central Turkey. It is an impression of a cylinder seal from the archaeological site of Arslantepe-Malatya, which appeared near of the named «Temple B». The archaeological layers were dated to 3374 BC using dendrochronology.Graphic on the Cornell University web site. The stamp shows a figure seated on a threshing board, with a clear image of the lithic flakes inlaid in the bottom of the board. The main figure is sitting (possibly on a throne) under a dossal. In front is a driver or oxherd, and there are peasants with pitchforks nearby. According to M. A. Frangipane, that the seal may illustrate a religious scene: