C5 - The Growing Environment /checked Flashcards
What five things does the vine need?
Heat Sunlight Water Nutrients Carbon Dioxide
What is photosynthesis?
Using sunlight to combine CO2 and water to produce glucose and oxygen.
Below what temperature is it too cold for a vine to grow?
10 C
What is the defining factor which grape varieties can be grown within a certain region?
Heat.
Not all varieties need the same amount of warmth during the growing season.
What is heat needed for?
flowering, fruit set and ripening.
Between what latitudes lie most vineyards? Why?
30 - 50 degrees.
These latitudes satisfy a vine’s need for warmth, but also winter dormancy.
How does temperature drop with altitude?
0.6 degrees C with every 100m increase in altitude
How do ocean currents affect climate/weather?
Large volumes of warm or cold water across the surface of oceans lead to localised warming or cooling.
Examples: Humboldt Current off Chile, Benguela Current off SA, Gulf stream NW Europe.
How does fog affect temperature? List two examples of areas where this is an important factor.
It cools an area.
California and Casablanca in Chile.
List the factors affecting heat
Latitude Altitude Ocean currents Fog Soil Aspect
What kind of soil absorbs and reradiates the sun’s heat?
Darker soils or those with a higher stone and rock content
How does soil with a high water content affect budburst?
It delays it, as it takes more energy to heat the soil and heat from the vines is conducted away more quickly
What is slope aspect?
The direction in which a slope faces.
How does aspect affect ripening?
Provide an example of a region which benefits particularly from a good aspect.
The side of a slope facing towards the equator receives more sunlight and heat.
The Mosel Valley.
How is continentality defined?
It is the temperature difference between the coldest and the hottest months.
High continentality = large differences in seasonal Temp
Low continentality = small differences in seasonal Temp
A region’s continentality will define the length of the growing season and it has impact on the total amount of heat available to a vine.
What is the main factor affecting continentality? Why?
Proximity of large bodies of water. They cool down and heat up slower than land masses.
What is Diurnal range?
The difference between daytime and night-time temperatures.
Why is a large diurnal range beneficial?
Cool nights help slow the loss of aromas and acidity in the grapes during ripening.
What is the impact on wine of a smaller diurnal range?
They are usually fuller bodied
What’s impacts diurnal range?
Proximity to seas and lakes Cloud cover (greater near seas and lakes)
What effect do warm nights have on a vineyard?
They help to accelerate ripening, particularly the production of sugar
At what low temperature is the vine at risk?
When the temp drops below -20 C. This can damage or kill a vine
What part of a vine is most at risk during winter freeze?
The graft
How can grafts be protected during winter freeze?
By covering up the graft with soil (earthing up)
What impact can a mild winter have on a vine?
It can prevent the vine from being dormant, and in the worst cases, the vine can produce more than one crop a year, shortening the vine’s life and reducing its quality
How else can mild winters be bad for viticulture?
Larger populations of pests can survive to attack the vines in the following summer
What is Spring frost?
Cold air below 0 deg C collecting at ground level and freezing any settled water vapour
What happens to a vine during spring frosts?
Newly burst buds or young shoots are killed by frost
What are the four main methods of protection against frost?
Heaters
Wind machines
Sprinklers
Vineyard design
Why/how do sprinklers work in frost protection?
When their water freezes, it releases latent heat, protecting buds and shoots
How can thoughtful vineyard design help to protect against frost?
Planting vines away from depressions, best on slopes.
Vines can also be trained high.
What negative effects do cold spring temperatures have on a vine?
Delayed budburst
Shortened growing season, grapes do not ripen
Smaller crop due to disrupted flowering and fruit set
What negative effects do very hot summer temperatures have on a vine?
During prolonged periods of extreme heat all vine activity will slow and eventually stop = no ripening
Name the three factors affecting sunlight.
Latitude
Seas and Lakes
Aspect
Explain the effect of latitude on sunlight. Give two places which benefit from this effect.
Day length during the summer season is longer, the further away from the equator a vineyard is.
Germany (Riesling) and Washington State (Cabernet)
Explain how proximity to large bodies of water can affect sunlight
Vineyards near seas and lakes tend to experience more cloud cover. Sometimes vineyards situated above rivers and lakes can benefit from reflected sunlight.
Which elements of aspect are favourable for the ripening of grapes?
Steeper slopes and facing toward the equator
What can happen to grapes if it is too sunny?
They can become sunburnt, resulting in bitter dark patches on grapes
How does a vine get water?
Rainfall
Irrigation
Water stored in soil/bedrock
What are the three main irrigation techniques?
Drip irrigation
Sprinklers
Flood irrigation
What is drip irrigation?
The most advanced and expensive form of irrigation.Each vine has its own dripper that can be computer controlled, ensuring that each vine gets an optimal amount of water.
What are the benefits and disadvantages of sprinklers as a form of irrigation?
They are a lot cheaper than drip irrigation, but they waste a lot of water and create damp conditions like rainfall, increasing disease-risk
What is the benefits and disadvantages of flood irrigation?
It’s very cheap, but only possible in flat or gently sloping vineyards where there is access to large quantities of water.
What happens if the vine has access to too much water during the growing season?
The vine will continue to grow shoots and leaves during the ripening season leaving less sugars for ripening grapes.
Shoots and leaves increase shading
Waterlogged can cause roots to rot
How can waterlogging be avoided?
Planting vines on a slope
On flat sites, installing drainage pipes
What is the potential impact of heavy rain shortly before harvest? How does this impact resulting wines?
Berries can swell, diluting flavours in the wines they produce
In extreme cases after rainfall, berries can split. What other hazard does this attract?
Fungal disease
What effect can summer hail have on a vine?
It can damage the grapes and even the vine itself, in worst cases, destroying an entire crop
Name an area particularly prone to hail.
Mendoza, Argentina
List 2 preventative measures against hail.
Netting
Geographical diversification
How is a region’s climate defined?
The annual pattern of temperature, sunlight and rainfall averaged out over several years
How is weather defined?
The annual variation that happens relative to the climatic average
When is the growing season in the Northern and the Southern Hemisphere?
Northern: April - October
Southern: October - April
In order, what are the temperature definitions laid out by WSET for ‘Cool’, ‘Moderate’, ‘Warm’ and ‘Hot’
Average growing season temperature 16.5 - 18.5 - 21.0
Cool: < 16.5C
Moderate: 16.5C - 18.5C
Warm: 18.5C - 21C
Hot: > 21C
List the three climate categories
Continental
Maritime
Mediterranean
List continentality, rainfall, temperature of growing season and sunlight of growing season for all three climate types…
Continental: High continentality, low rainfall, cool, moderate, warm or hot temp and usually very sunny
Maritime: Low to medium continentality, medium to high rainfall, cool or moderate temperature and cloudy
Mediterranean: Low to medium continentality (precipitation mostly in winter), moderate or warm temperatures and usually sunny
When typically does the temperature rapidly drop in a continental climate?
Autumn
What kind of varieties are best suited to cool continental climates?
Ones that bud late and ripen early
What climates experience very dry summers?
Continental
When does it rain the most in a maritime climate?
It rains evenly throughout the year
What effect does the year-round rain in a maritime climate have on other climatic features?
It moderates sunlight and temperature
How does a maritime climate affect the length of a growing season?
It lengthens it as a result of its moderating effects
Name the biggest hazards of a maritime climate
Spring and summer rains, which can be a very significant risk to the flowering, fruit set and health of the grapes at harvest
What is Humus?
Decomposing Plant and Animal matter
What are the three major components of soil?
Tiny soil particles
Stones and rocks
Humus
Where do soil particles, stones and rocks come from?
The underlying rock or later deposits laid on top of it
What are the largest types of soil particle?
Stones
What are the smallest soil particles?
Clay
From a viticultural point of view, what are the disadvantages of large soil particles?
They are poor at holding water and plant nutrients
What are the benefits of Humus?
It is rich in plant nutrients and had excellent water retaining properties
How should water supply to a vine ideally vary over the growing season?
A good supply early on to support growth, then mild water stress after veraison to benefit ripening
How is water stored in the soil?
By binding with clay particles or humus. It may be accessible in the underlying rock, too.
Too much clay: waterlogging
Too much sand/rocks: insufficient water is retained
Describe the ideal soil for viticulture
This would be a mixture of sand and clay particles, known as LOAM.
It has relatively few nutrients and iswell drained, but able to store enough water to support the vine through the growing season
What are the most important nutrients for vine?
Nitrogen
Phosphorus
Potassium
What will happen to a vine exposed to too-high levels of nutrients?
It will grow too vigorously and create too much shade
What is the most common symptom linked to nutrient deficiency?
Chlorosis
What is Chlorosis?
The leaves turning yellow because they lose chlorophyll. Photosynthesis becomes restricted and grape quality/yield is affected.
What’s the most common cause of Chlorosis? What sort of soil is most likely to cause this?
The inability of a vine to gain sufficient iron from the soil. Soils with high limestone content.
