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.