Measure of area with 10,000 m² (roughly equivalent to a football pitch 120 x 80 m); one square kilometre is 100 hectares. The word hectare is composed of the Greek hekt(o) for "hundred" and ar and means 100 ar. Hectare is commonly used in European viticulture to indicate the area under vines. The maximum yield of wine, defined differently according to the wine laws of the individual countries per region, area or appellation, is expressed in hectolitres (100 litres) of grape must or kilograms of grapes per hectare (yield per hectare). The acre, which is common in England and the USA, corresponds to 0.405 hectares (just under 2.5 acres/ha). A hectare consists of four acres (old measure of area). See also the world ranking list of grape varieties according to area under grape variety, as well as other common units of measurement under area measures and gauges.
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