The word Trillo comes from the verb trillar, which means to thresh, hence the trillo is a threshing board.
The trillo is a basically now obsolete but used to be used to separate cereals from their straw. It is a thick board, usually made of two to six pieces, with a fairly rectangular shape, but the front end is narrower than the back end. It is also slightly curved upward
The pieces of wood are joined together and covered with small stone shard or flint, or sometimes razor sharp metal blades
Normally around 1 meter wide and 2 meter deep, the boards have a ring attached which was used to attach rope to the horses or mules, who then walked in circles over the cereal spread on the threshing room floor. The farmer was usually sat on the board and if additional weight was needed, would add large stones or children!
As it moved in circles over the cereal, the stone chips or blades would cut the straw and ear of the wheat thus separating the seed without damaging it.
Craftsmen who made the threshing boards were known as ‘briqueros’ and the specialized skills of adding the flint were passed from father to son. The most famous town for this work was Cantalejo in Segovia and they captured nearly all the sales of the boards in the local regions of Castile and León, and as far away as Madrid, Castile-La Mancha, Aragon and Valencia
The threshing board can sometimes still be seen in regions of Spain, however most of the work done by the trillos is now replaced by combined harvesters and the trillo is relegated to part of folklore celebrations or has become a table or ornament in someone’s home.