WSET3 Viticulture Flashcards
Typical maritime- climate regions
Bordeaux
Eastern coast of New Zealand
Northern Portugal
Important environmental needs for vines
Sunlight, water & carbon dioxide - photosynthesized by Chorophyll to produce glucose
CO2 always available, so only sunlight and water matter
Vines’ dormancy temperature
10 C
Vine growth to peak temperature
22-25 C
Growing season in the northern hemisphere
April to October
Growing season in the southern hemisphere
October to April
The annual weather pattern of an area averaged over several years
Climate
Climate parameters
Rainfall Temperature
Regional climate classification (by temperature)
Cool - 16.5 C or lower
Moderate - 16.5 C - 18.5 C
Warm - 18.5 C - 21 C
Hot. 21 C+
Typical cool-climate regions
Champagne
Mosel
Southern England
Anderson Valley
Tasmania Carneros
Cool-climate wines
Early ripening varieties
e.g. Chardonnay, Pinot Noir
Basic building block of the vine
GLUCOSE
Combines to produce cellulose for roots, trunks, shoots, leaves and fruit
Tannins, acids and flavor molecules in the grape
Typical moderate-climate regions
Bordeaux
N Rhone
Rioja
Piedmont
Tuscany
Coonawarra
Marlborough
Napa & Sonoma
Moderate-climate wines
Medium-bodied wines from intermediate-ripening varieties e.g. Cabernet Sauvignon, Merlot, Sangiovese
Typical warm-climate regions
S Rhone
Douro
Jerez
McLaren Vale
Paarl
Warm-climate wines
Heat-loving varieties e.g. Grenache, Mourvedre, Ruby Cabernet
Fortified wines
Typical hot-climate regions & wines
San Joaquin Valley, CA
Table & Drying Grapes
Define Continentality
Difference between the average mean temperature of the hottest month and the coldest month
Regional climate classification
(by degree of “continentality”)
Maritime
Mediterranean
Continental
Tropical
Maritime climate characteristics
Low annual range of temperature
Warm summers and mild winters
Relatively high rainfall and cloud cover
Near large bodies of water
Maritime-climate wines
Medium-bodied wines with moderate alcohols
e.g. Bordeaux reds and whites, Muscadet, Rias Baixas, Vinho Verde
Mediterranean climate characteristics
- *Low annual** range of temperature
- *Warm** sunny summers and mild winters
- *Dry** summers with most rain in winters
- *Long growing season**
Typical Mediterranean- climate regions
Mediterranean
West coast of the United States
Chile
SE Australia
W Cape, S Africa
Continental climate characteristics
Wide annual range of temperature
Hot summers and cold winters Inland
Dry
Short growing season
Mediterranean-climate wines
Full-bodied, rich-textured reds with ripe tannins
Typical cool continental- climate regions
- continentality and long day length
- cool autumns
Burgundy
Champagne
Northern regions of Germany British Columbia
Alsace
Austria
Grapes in regions with continentality and long days
Early-ripening varieties
- Riesling
- Pinot Noir
Cool continental-climate wines
Intensely-flavoured, late- harvested whites
High alcohols,
Sweet wines
Typical warm continental-climate regions
Mendoza
Central Europe
Central Spain
Warm continental- climate wines
- long warm autumns
Malbec
Cabernet Saurignon
Tropical climate characteristics
Minimal annual range of temperature
Hot summers and warm winters
Rainfalls more deciding factor
Unsuitable for high quality viticulture
Shortened vine productive lifespan
Brazil India Thailand
What is aspect? How does it affect a vineyard?
Direction a vineyard slope faces
- an important characteristic of a vineyard site
- determines exposure to sun
Preferred aspect in cool climates in northern hemisphere
South facing
- warmer
- aiding the ripening process
What is slope? How does it affect a vineyard?
Degree of incline
- determines intensity of sunlight received
Advantages of east facing vineyards
Sun’s rays scattered less in the morning, when the earth has cooled overnight, and dust has settled
Disadvantages of west facing vineyards
Sunlight scattered more by dust that has been lifted by warming air during the day; Face damper, cooler prevailing weather conditions
Aspect and slope for locations that would otherwise be too hot
Slopes that face away from the equator
Influence of slope or incline on a vineyard
Sunlight interception
Air movement
Soil properties
Cost of working the land
Advantages of sloping vineyards
Air movement on slopes (i.e. cold and dense air move downhill displacing warm and less dense air to produce warm thermal layers on the slope) deters frost and offers slightly improved ripening potential;
Soils on slopes tend to be poorer, more coarse for better drainage
Disadvantages of sloping vineyards
Increased risk of erosion;
Higher costs (manual), e.g. the Mosel Valley
Ideal vineyard sites
Isolated hills
- no big currents of colder air flowing down from the main hills
e.g. Burgundy’s hill of Corton at Aloxe-Corton, Montagne de Reims in Champagne
Effects of canopy management
Affect climate in the fruiting zone, therefore style and quality of wines
Effects of thick vigorously-growing canopy in cool-climate regions
Reduce flower initiative and berry set due to shading; Higher acid retention due to cooling;
Reduce sugar accumulation due to humidity & shade; Encourage competition for sugar
Temperature’s effects on yield
Rate of growth;
Number of flower clusters and size;
Success of the setting of flowers into berries
Conditions for finest tastes and aromas
Slow, cool, berry ripening
Temperature’s effects on quality
Level of yield;
Accumulation of sugars and reduction of acidity; Development of wine aromas Phenolic ripeness (tannins)
Disadvantages of excess rain
- Cool the mesoclimate;
- More difficult for machinery to work;
- Increase risk of fungal disease; Reduce fruit set (esp. in low temp);
- Brunch compaction and berry splitting;
- Dilute must if rains before harvest
Purpose of sunlight
Energy source for vines to build sugars
Increase temperature of vineyard
Effects of sunlight in cool temperature
Rate of photosynthesis slows; Increase leaf area and canopy to compensate;
Exposure of fruit to sunlight enhance ripening;
Eliminate pyrazines in Bordeaux varieties
Exposure of fruit to sunlight
Increase rate of ripening;
Increase risk of sunburn;
Effect of day length
(photoperiod)
Regions in high latitudes have longer summer days (more exposure to sunlight) to offset lower temperatures
e.g. Mosel, S England, Central Otago
Effects of sunlight on yield and quality
Amount of sugar produced by photosynthesis
- warm & cloudy (Hunter Valley) –> low sugars;
- cool & sunny (Central Otago) –> high sugars
Sunlight required for vitis vinifera
> 1250 hours of sunshine to produce ripe fruit
Geographical features affecting climate
Bodies of water;
Ocean currents
Forest
Altitude and mountain ranges
Advantages and disadvantages of proximity to water
Pro:
Store of heat,
Reflects sun’s rays,
Source of irrigation,
Reduce risk of ground frost
Morning mist for “Noble Rot”
Cons:
Increased humidity; eg potential fungal disease (downy mildew)
Effects of ocean currents
Create cooling mists and fogs
e.g. Pacific Ocean current off California; Humbolt current off Chile
Warm up the climate
e.g. Gulf stream on west coast of UK
Proximity to forests
Pros: windbreaks; store heat; reduce erosion
Cons: cool the mesoclimate in warm weather and increase humidity; birds
Effects of altitude
Mean annual temp decreases by 0.6 C for every 100m rise in altitude (or a reduction of 105 degree-days a year)
Increase the cooling effects of wind exposure
Mountain ranges
Protection from excessive wind and rain (rain shadow)
e.g. Alsace & Vosges mountains
Purpose of soil
Support vine; Provide nutrients
Soil characteristics
Nutrients
Pets & rootstock
Water holding capacity and availability Heat retention
Fertility
Soil fertility
Soil texture
Soil structure
Organic matter content Mineral content Availability of air and water Level of acidity/akalinity
Soils with low fertility
Vines grow best on these soils - restrict canopy growth;
- often stony and well-drained
Heavy soils
High clay or silt content
Hold more water
Lighter soils
More sand and gravel
ore free-draining
Advantages of clay soils
More moisture More nutrients (negative charge)
Disadvantages of clay soils
Take longer to heat up in spring and tend to be colder all year round (coz water);
Swell when they absorb water and shrink when dry leading to cracking and water loss;
Sticky when wet;
Wet clay soils’ structure deteriorates when worked
Loam
Balanced mixture of clay, silt and sand Both nutrient holding abilities of clay and good drainage of sand
Soil types
Limestone
Chalk
Slate
Granite
Volcanic rocks
Limestone
Sedimentary rock from deposition of shells & skeletons of marine life; mainly calcium carbonate; alkaline & free draining
e.g. central and eastern Loire, Piedmont, N Spain, Burgundy, Limestone Coast Zone in S Australia
Limestone-rich soils inhibits uptake of iron & other micronutrients (risk of chlorosis)
Chalk
Lower density than limestone; better drainage
e.g. Champagne, Jerez
Other sedimentary rocks
Dolomite - similar to limestone but with high level of magnesium
Sandstone - compressed sand and quartz
Shale - soft clay
Slate
Shale that has been altered by high pressures and temperature;
harder and less porous than shale;
heat retention
e.g. Mosel
Granite
Igneous rock from solidified magma from volcanoes; extremely hard and desnse but free-draining
e.g. Baden, N Rhone, Beaujolais
Volcanic rocks
Lava on surface
e.g. Santorini, Madeira
Humus & Benefits of humus
Partially decomposed organic matter
maintain soil structure; retains nutrients; holds water;
low plasticity and cohesion for easier soil management; gradual release of nutrients as humus slowly mineralised; darken colour to retain heat
Macronutrients
N - plant cells, nucleic acids, chlorophyll and hormones; second to water for plant growth
P - energy fixation, root growth, ripening K - regulate flow of water and sugar, ripening
Ca - regulate cell acidity, cell walls
S - amino acids and enzymes
Mg - chlorophyll, regulate acidity, sugar metabolism, ripening
Parts of the vine
Roots - absorb water and nutrients, anchor vine, store carbohydrates
Trunk/arms (Permanent Wood) - more than 1 year old; restricted by pruning; transport water, store carbohydrates
Shoots (one year old wood) - support leaves & buds.
Nodes - from where leaves, flowers and tendrils grow
Buds - prompt, latent/dormant
Leaves - photosynthesis, transpiration
Petioles - leaf stalks (petiole analysis for nutrients)
Flowers - reproduction, hermaphroditic, inflorescences
Tendrils - “fingers” that hold on to trellis wires, cannot support themselves
Berries - inflorescenes, attract birds
Growth cycle of the vine
Budburst - April/May (Sep/Oct)
Shoot growth - May/Aug (Oct/Jan)
Flowering and fruit set - Jun/Jul (Nov/Dec)
Berry growth & veraison - Jul/Sep (Dec/Feb)
Wood ripening - Sep/Nov (Feb/Apr)
Berry ripening - Sep/Nov (Feb/May)
Winter dormancy - Nov/Jan (May/Jul)
Veraison
Berry skins change colour
Translucent for white varities
Red for black varieties
Most important stages in the growth cycle
Floral initiation (depend on temp and sunlight)
Budburst (affected by spring frosts)
Flowering (temp, affected by rain)
Fruit set (coulure = failure of berries to set)
Shoot growth (in balance with yield)
Berry ripening (sugar/physiological ripening)
Life cycle of the vine
Yr 1-3 Trunk/Wood (Vegetable growth/drop fruit)
Yr 3-4 1st Crop (good fruit to leave balance)
Yr 7-20 Wood thicken (vigorous vine/high yield)
Yr 20+ Yield decline (vielles vignes, alte Reben)
Criteria for vine selection
Adaptation to the climate: cold, short growing season, drought etc
Resistance to disease: phylloxera, nematodes, mildews, oidium, botrytis
Adaptation to the soil conditions: lime, drought, acidity, salt (most important for rootstocks)
Economic characteristics: high yield, high quality, suitablity for mechanisation
Clonal selection
Vines taken from one parent (genetically identical)
Criteria
- yield, fertility, berry size, sugar, acidity, colour, flavour, aroma, disease, drought, virus free, ease of grafting, cost
Crosses
Intraspecific
New variety is produced from two parents of same species (eg V Vinifera)
CAbSav = CabFranc x SavBlanc
Muller-Thurgau = Riesling x Madeleine Royale
Disadvantages of clonal selection
Spread of disease
Limited to certain regions
Limited to certain styles Overproduction
Reduction in vine genetic resources
Hybrid
Interspecific
Usually 1 American as parent with V Vinifera (such as Vidal )
Reasons for hybridisation
- Phylloxera & Downy Mildew (Plasmopara viticola)
- winter cold resistance
Layering
Canes are buried in the ground and then separated from the parent plant once they have established their own roots
Vitis berlandieri and rotundifolia
Vitis vinifera only layered in Phylloxera- free soils
Cuttings
Pieces of parent plant develop into new plants
Hardwood winter cuttings from canes (carbohydrates)
Cuttings 30-45 cm in length
Stored at 5 C prior to grafting
Heat treated at 50 C for 30 mins (pests, virus)
Grafting
Vinifera scion grafted onto American rootstock
Purpose
- Phylloxera, Nematodes
- soil conditions (lime)
- high or low vigour
- change varieties (top or head-grafting)
Grafting methods
Field grafting:
Bench grafting (in nursery)
Whip (by hand)
Omega (by machine)
Top grafting:
chip-budding
T-budding
cleft-grafting
Key environmental and financial factors for site selection
Water availability
Regional climate (temp & sunshine hour)
Soil type and quality
Access to the site
Availability of labour and resources
Proximity to market
What is a trellis?
A physical structure, consisting of posts and wines that largely supports the grapevine framework (canes, shoots, foliage)
Simple: low vigor, low potential site
Complex: high vigor sites, disease control
What factors affect the choice of a trellis system?
Legislation
Geographical features of site
- topography
- wind
- rainfall
- temperature
- frost risk (higher trellis at bottom of slope)
- soil fertility
Effectiveness of light interception
Cost/time (establishment and maintenance)
Mechanical potential
Popularity and attractiveness
Untrellised
S Europe
bush (trunk trained short)
no trellis
spur-pruned (bush vines or gobelets) cane-pruned (basket; Santorini, Greece)
- *Pros**: low cost
- *Cons**: low yields, disease, manual
Staked vines
Cote Rotie, S France, Spain, Portugal, Italy, California, S Africa
Post to support vine
Trained higher than bush
Trained to form a crown (head) 20-30 cm above the ground
Spur-pruned without a crown
Pros: air circulation -> less disease
Cons: low yield, not for high vigor sites
Single wire
Cordon trained and spur pruned Head trained and cane pruned
Pros: continuous foliage, inexpensive
Cons: new shoots hang down -> sunburn
Two-wire, vertical
California in mid-1980s
Most basic form of multi-wired trellis system
Single fruiting wire, single foliage wire above
Pros: mechanical pruning and harvesting
Vertical shoot position (VSP)
France, Germany, cooler regions of Austalia and NZ
Places with high risk of fungal diseases
Non-divided canopy
Movable foliage wires
Cane-pruned (guyot)
Spur-pruned (unilateral/bilateral cordons)
Pros: mechanical operations & harvest
Cons: high shoot density, not for high vigor varieties and high potential sites
Pergola/tendone trellis
Chile, Agentina, Italy, Portugal
Table grapes
2m high trunks
Cane or spur pruned
Cons: high cost of construction/maintenance; not for high potential sites; shading problems (powdery mildew, botrytis)
When is terracing needed?
Slope over 20 degrees
Why pruning and training?
- *Un-pruned vines**
- irregular yields
- high-acid, low-sugar berries
- *Pruning and training to increase yield/quality**
- balance between fruit and leaf
- ideal canopy (15 shoots/m; 1-1.5 leave thick)
- shoot about pencil thick, 12-15 nodes long
- appropriate crop size
- trellis to capture max sunlight
- avoid leave bunching/disease risk - uniform bunch ripening
- allow mechanical spraying and harvesting
- young vines pruned lightly with flower removed
- older vines pruned lightly to raise crop
What is canopy management?
Organisation of the shoots, leaves and fruit of the grapevine to maximise the quality of the microclimate of the leaves and fruit to improve quality and yield and to minimise disease risk.
Where is it importance?
- cool-climate regions
- New World: high vine vigor in fertile soils
Main aims of canopy management
Max light interception
- large canopy surface
- early development of canopy in spring
- avoid inter-row shading (1:1 height:alley width)
Min canopy shading
- shaded leaves use, rather than produce energy
- Dr Richard Smart: vegetative cycle
Uniform microclimate for fruit
Balance between fruit and leaf
Min disease
Mechanization (pruning, pesticide, harvesting)
Types of Irrigation
Flood - lots of water required; desert areas for bulk wine eg Argentina
Sprinklers - effective for large vineyards; cheap to instal; frost control; induce noble rot Cons: water waste; fungal disease; labour intensive (traveling sprinklers)
Drip - better control of water supply; save water. Con - expensive, constant monitoring
Pests
Phylloxera - nematode destroyed 2/3 of V Vinifera, eats roots
Nematodes - microscopic worms, can transmit vine virus, need to sanitize soil before planting
Birds/animals - eaten off vine can lead to fungal disease for 1/2 eaten grapes. Netting is the best option for birds. Fences for animals
Insects - feed on grapes and leaves. Either use insecticides or integrated pest management eg introducing predators of pests
Fungal Disease
Downy & powdery mildew - thrive in warm, humid conditions. Attacks green shoots & leaves Leaves: yellow oil spots, white downy patches. Lives in the tissue (not on surface); Flowers dry up and drop off; Berries go grey
Grey Rot: Botrytis Cinerea (same as Noble Rot); High humidity and warm temp; Enter vine through wound; Attacks leaves & fruit; Brown then black patches; Berry infections most serious
Affect tight clusters from middle outward
Prevention: canopy management to open air flow and keep as dry as possible; spraying at flowering
copper salts (preentative); organic and systemic pesticides
