The grass (eg grazing) in Groningen is an old Dutch surface area.

One grass is the amount of grass needed for a cow and was just under half a hectare. This thus amounts to two cows per hectare, while currently three or more cows per hectare are kept. The size

An exact size can not be mentioned. Attempts have been made to calculate what this would have been. Per area (village), the size of the area is divided by the grastal. Strikingly, the plots always have full (sometimes half) grazing. It seems that the number of cows that crashed was calculated. If there were two, then the plot was 2 degrees wide. If there was a calf, it would be 2½. The grastal was mainly of importance for the land tax (the pounding). One paid a certain amount per grass. Therefore, an accurate determination was not really necessary. Toponiem

Field names referred to the size of a lot. The high four is, for example, a 4-degree land or four cows grazing.

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