viticulture Viticulture (, "vine-growing"), viniculture (, "wine-growing"), or winegrowing is the cultivation and harvesting of grapes. It is a branch of the science of horticulture. While the native territory of ''Vitis vinifera'', the common grape vine ...

, the yield is a measure of the amount of

grape A grape is a fruit, botanically a berry, of the deciduous woody vines of the flowering plant genus ''Vitis''. Grapes are a non- climacteric type of fruit, generally occurring in clusters. The cultivation of grapes began approximately 8,0 ...

s or

wine Wine is an alcoholic drink made from Fermentation in winemaking, fermented fruit. Yeast in winemaking, Yeast consumes the sugar in the fruit and converts it to ethanol and carbon dioxide, releasing heat in the process. Wine is most often made f ...

that is produced per unit surface of

vineyard A vineyard ( , ) is a plantation of grape-bearing vines. Many vineyards exist for winemaking; others for the production of raisins, table grapes, and non-alcoholic grape juice. The science, practice and study of vineyard production is kno ...

, and is therefore a type of

crop yield In agriculture, the yield is a measurement of the amount of a crop grown, or product such as wool, meat or milk produced, per unit area of land. The seed ratio is another way of calculating yields. Innovations, such as the use of fertilizer, the ...

. Two different types of yield measures are commonly used, mass of grapes per vineyard surface, or volume of wine per vineyard surface. The yield is often seen as a quality factor, with lower yields associated with wines with more concentrated flavours, and the maximum allowed yield is therefore regulated for many wine

appellation An appellation is a legally defined and protected geographical indication used to identify where the ingredients of a food or beverage originated, most often used for the origin of wine grapes. Restrictions other than geographical boundaries, s ...

Units and conversions

In most of

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

, yield is measured in

hectoliters The litre (Commonwealth English, Commonwealth spelling) or liter (American English, American spelling) (SI symbols L and l, other symbol used: ℓ) is a metric units, metric unit of volume. It is equal to 1 cubic decimetre (dm3), 1000 cubic c ...

per

hectare The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), that is, square metres (), and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. ...

, i.e., by the volume of wine. In most of the

New World The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: ...

, yield is measured in tonnes per hectare (or short tons per acre in the USA) – i.e. by mass of grapes produced per unit area. Due to differing

winemaking Winemaking, wine-making, or vinification is the production of wine, starting with the selection of the fruit, its Ethanol fermentation, fermentation into alcohol, and the bottling of the finished liquid. The history of wine-making stretches over ...

procedures for different styles of wine, and different properties of different grape varieties, the amount of wine produced from a unit mass of grapes varies. It is therefore not possible to make an exact conversion between these units. Representative figures for the amount of grapes needed for 100 L of wine are 160 kg for

white wine White wine is a wine that is Fermentation in winemaking, fermented without undergoing the process of Maceration (wine), maceration, which involves prolonged contact between the juice with the grape skins, seeds, and pulp. The wine color, colou ...

, 130 kg for

red wine Red wine is a type of wine made from dark-colored grape varieties - (red grapes.) The color of the wine can range from intense violet, typical of young wines, through to brick red for mature wines and brown for older red wines. The juice fro ...

, and 140 kg for a mixture of red and white wine. Thus: * for white wine, 100 hl/ha ≈ 16,000 kg/ha (16 t/ha) = 6.5 tons per acre. ** 1 ton per acre = 2470 kg/ha ≈ 15 hl/ha * for red wine, 100 hl/ha ≈ 13,000 kg/ha (13 t/ha) = 5.3 tons per acre. ** 1 ton per acre = 2470 kg/ha ≈ 19 hl/ha * for mixed wine, 100 hl/ha ≈ 14,000 kg/ha (14 t/ha) = 5.7 tons per acre. ** 1 ton per acre = 2470 kg/ha ≈ 17.5 hl/ha

Typical yields

Yields vary greatly between countries, regions and individual vineyards, and can be vintage-dependent. Somewhere around 50 hectoliters per hectare, or 3 tons per acre, is a typical representative figure for many countries and regions.

Yield as an indication of quality

While yield is generally seen as an important quality factor in wine production, views differ on the relative importance of low yields to other aspects of vineyard management. In general, there is consensus that if vines are cropped with a very high amount of grape clusters, a poor wine will result because of slow and insufficient ripening of the grapes, due to an unfavorable leaf to fruit ratio. This is a situation that would typically correspond to yields of, say, 200 hl/ha or more, depending on grape variety and many other factors. Beyond that, there are differing schools of thought. One school of thought, generally subscribed to in France, claims that great red wine is impossible to produce at yields exceeding 50 hl/ha. Another school of thought claims that a yield of 100 hl/ha is possible to combine with high quality, provided that careful

canopy management In viticulture, the canopy of a grapevine includes the parts of the vine visible aboveground - the trunk, cordon, stems, leaves, flowers, and fruit. The canopy plays a key role in light energy capture via photosynthesis, water use as regulated ...

is used. In general, white wine is seen as less sensitive to high yields, and some grape varieties, such as

Pinot noir Pinot noir (), also known as Pinot nero, is a red-wine grape variety of the species ''Vitis vinifera''. The name also refers to wines created predominantly from Pinot noir grapes. The name is derived from the French language, French words fo ...

, as particularly sensitive to overcropping. Many examples exist where a vintage-to-vintage variation of yields is in fact positively related with quality, since the low yields can be due to loss of grapes due to adverse conditions such as

hail Hail is a form of solid Precipitation (meteorology), precipitation. It is distinct from ice pellets (American English "sleet"), though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailsto ...

or grey rot. For the

Bordeaux Bordeaux ( ; ; Gascon language, Gascon ; ) is a city on the river Garonne in the Gironde Departments of France, department, southwestern France. A port city, it is the capital of the Nouvelle-Aquitaine region, as well as the Prefectures in F ...

vintages of the 1980s, it is generally recognized that the most abundant harvests also gave the best vintages.

Regulation of yields

In both France and Italy, the maximum allowed yields are regulated in

wine law Wine laws are legislation regulating various aspects of production and sales of wine. The purpose of wine laws includes combating wine fraud, by means of regulated protected designations of origin, labelling practices and classification of wine, ...

s, and vary between appellations. In France, the maximum yields are given in the regulations for each ''

appellation d'origine contrôlée In France, the ''appellation d'origine contrôlée'' (, ; abbr. AOC ) is a label that identifies an agricultural product whose stages of production and processing are carried out in a defined geographical area – the ''terroir'' – and using ...

'' (AOC). The maximum allowed yield for given AOC in a given vintage is a combination of the base yield of the AOC, as modified by the ''plafond limité de classement'' (PLC), which is percentage set for each vintage. In most vintages, the PLC allows a production around 20 per cent above the base yield.

References

{{portal bar, Drink Viticulture Wine terminology