Viticulture Scenarios Flashcards
Highlight a scenario that illustrates the factors that influence the grape growing in Prioriat, Catalunya?
Priorat is located in Catalunya in north-east Spain. Although there are variations in different subzones, in general Priorat experiences very hot, dry summers and cold winters. The area is so hot and sunny that the best vineyards are planted on slopes facing north-east to protect the vines from the most extreme afternoon heat. The soils in Priorat are stony slate and quartz. There is little organic matter and so the soils are low in nutrients but free-draining. Irrigation is not permitted, and the hot, dry conditions result in a high evapotranspiration rate. Overall, this means that the vine struggles to obtain enough water.
The vigour of vines and their yield are naturally limited by the lack of water and soils that are poor in nutrients. The individual vines are therefore relatively small and the training and pruning options reflect this. Most of the vines in this region are bush vines. These are well adapted as the shoots and leaves provide some shading for the grapes in this hot and sunny location, but the vines are not so vigorous that excessive shading becomes an issue. The vines are planted at low density (often around 2500–3000 vines per hectare) so the roots of each vine can grow over a large area in search of water and nutrients. Yields are also extremely low due to the number of old vines in the region. Yields are approximately 15–25 hl/ha, but may be lower in some vineyards.
Garnacha and Cariñena are the most widely planted grape varieties. They are suited to the extreme conditions as they are late ripening (so they do not reach sugar ripeness too quickly) and drought tolerant. A grape grower based in this area may also choose to use a drought tolerant rootstock such as 140R.
Because Priorat’s terrain is extremely rugged and the vines are often not trellised, the work in the vineyard, including harvesting, needs to be carried out by hand. Low yields and the need for long hours of manual labour means that the wines from Priorat will never be inexpensive and often sell at premium or super-premium prices.
Highlight a scenario that illustrates the factors that influence the grape growing in Pauillac, Bordeaux?
Bordeaux is in south-west France near the Atlantic Ocean, which moderates its climate. It has moderate summers and mild winters, with rain throughout the year. The soils in Pauillac are free-draining and poor in nutrients.
Cabernet Sauvignon is the main grape variety. It is medium to late ripening and so can struggle to ripen in Bordeaux’s coolest sites and years. It can also lack some body and a diversity of fruit aromas/flavours. However, it can be blended with Merlot, which ripens earlier and adds body and fruit.
The vines are typically trellised to a VSP system. Poor, free-draining soils limit the vigour of the vines, so more complex systems of training for big vines would not be suitable. The vines are usually head-trained and replacement cane-pruned. The VSP system ensures that the canopy is appropriately arranged: the grapes are exposed to the sun, the surface area of the leaves is maximised and air circulation is improved, which helps to reduce onset of fungal diseases, all promoting the production of healthy, ripe grapes.
The vines are planted at high densities, for example with spacings of 1 m by 1 m (around 10 000 vines per hectare). Rainfall is high enough for vine competition not to be a problem. The vineyard land in Pauillac is expensive, so maximising the yield per hectare by planting vines closely makes economic sense. Yields often vary depending on vintage conditions, but average yields are generally 50–60 hl/ha (hence yield per vine is small).
Vine trellising means that some vineyard procedures, such as trimming and weed management, can be done by machine (specialised machines are able to straddle rows of vines and therefore be used despite tight between-row spacing). Harvesting may be carried out by hand or machine.
Highlight a scenario that illustrates the factors that influence the grape growing in Finger Lakes, New York State?
The Finger Lakes is an American Viticultural Area (AVA) region located in upstate New York. The deep lakes in the region provide some moderation of temperatures (V. vinifera would not be able to grow here without the effect of the lakes), but summers are still moderate and winters are extremely cold.
The vineyards are located around the edges of the lakes. In general, the black grape varieties such as Cabernet Franc are grown on the land nearest the lakes to benefit from the slightly more moderate conditions. This extends the period over which grape growing is viable, providing more chance for the tannins and aromas in these varieties to get ripe.
The main grape variety in the region is Riesling, its winter hardiness means it can survive harsh winters. However, grape growers will also hill up the soil so that it covers and protects the vine graft, which is generally the part of the vine that is most at risk from winter freeze. Riesling is also a late budding variety, which provides protection against spring frosts. A variety of clones of Riesling are typically planted to provide blending options to enhance the quality of the final wine or as one way of providing differentiation between different Rieslings in a winery’s portfolio.
The soils of Finger Lakes are nutrient-rich and that, together with plentiful rainfall throughout the year, means that the vines can be vigorous. Scott-Henry trellising systems are used to divide the vine canopies and hence improve light interception in large canopies. Various summer pruning techniques (e.g. leaf stripping) may also be carried out to enhance ripeness.
Rainfall in the growing season means that fungal diseases can be a problem. The divided canopy of Scott-Henry also improves air circulation through the canopy to reduce the risk, but spraying with fungicides is usually necessary also.
Large vines need sufficient space so that they do not overlap, so vine densities here are low (around 2800-3200 vines per hectare). Between-row spacing is also large to allow for mechanisation because labour availability is low. However, each vine can ripen a large crop, so yields are around 50-60 hl/ha.
Highlight a scenario that illustrates the factors that influence the grape growing in Central Valley, California?
Central Valley is an area in California that grows large volumes of grapes for inexpensive, high- volume wines. Because the grapes are used to make inexpensive wines, the key concern of the grape grower will be to maximise the yield of grapes while keeping costs low in order to maximise profit.
Located in inland California, the Central Valley has a warm, dry, sunny growing season. Although rainfall is a limiting factor, irrigation is permitted and provides the vines with their water requirements. Levels of nutrients will vary according to the soil and how the vineyard has been managed in the past, but fertilisers can be added if nutrients are limited. These factors combined mean that vines can grow large and ripen large crops of fruit. This is beneficial as vines are expensive to buy and therefore the most cost-effective option for the grape grower is low density planting (around 1200–1800 vines per hectare) of big, high-yielding vines (approximate yields 180-200 hl/ha).
In such conditions a large range of grape varieties can ripen. The choice of grape variety will typically be based on market demand and the price (e.g. per kilo) that the grape variety can command.
California sprawl is a common trellising technique in this area. The vines are typically spur- pruned and cordon-trained because replacement cane pruning requires more-skilled labour. In this trellising system, the vines are trained relatively high. A single wire is installed above the cordon and the shoots flop up and over the wire. This trellising technique is cheap compared to other trellising. The hanging shoots also help shade the fruit from intense afternoon sunshine, reducing risk of sunburn. Complex vine trellising systems such as Lyre system are also sometimes used to manage the vigour of the vines. Summer pruning techniques such as leaf pulling require labour or machinery and therefore are generally not carried out. In particular, green harvesting, which requires dropping fruit, is unlikely as this would reduce yields. Overall, the lack of passing through the vineyard and attention to individual vines may result in variable ripeness within the crop of grapes, and therefore lower quality.
Harvesting will typically be carried out by machine, which is generally the most cost-effective option for large vineyards. Where possible, the fruit may be picked at night so that the grapes are cool during transportation, reducing chance of oxidation and microbial spoilage. However, if there is a large amount of fruit to pick over a short period, this may not always be possible. The main concern of the grape grower will be providing a crop that is healthy and unaffected by rot; this means that the grapes may be picked relatively early to avoid any risks of rain as autumn approaches. If the grape grower also grows higher quality fruit, this make take preference when deciding when to pick, and therefore the grapes may not be picked at optimum ripeness.
