Free Flashcards DipWSET D1: Wine Production – 1/Vines

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[h] DipWSET D1 SET 1 Vines

[i] DipWSET D1 – Wine Production Flashcards

SET 1 Vines

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[start]

[q] When are vines dormant in the Northern and Southern Hemispheres?

[a]

Northern Hemisphere: November – March

Southern Hemisphere: May – September

[q] Below what temperature do vines go dormant?

[a] 10ºC (50ºF)

[q] At what temperature does freeze injury/damage occur?

[a] -20ºC (-4ºF)

[q] Temperatures below −___°C (−___°F) will kill most V. vinifera

[a] −25°C (−13°F)

[q] Vineyards facing west, which get afternoon sun, can experience what issues?

[a]

Vineyard may become too hot, particularly if it’s in a warm climate;
Grapes face increased risk of sunburn.
In certain climates, west-facing vineyards tend to endure damper, cooler weather conditions

[q] What are two advantages of sloping vineyards?

[a]

Cold, dense air moves downhill displacing warmer air to higher levels, which produce warm thermal layers on the slope (like the Côte d’Or).
Soils on slopes tend to be poorer, more coarsely textured and better drained

[q] What are some disadvantages of sloping vineyards?

[a]

Increased risk of erosion;
Higher costs as it requires hand harvesting

[q] What are four advantages of vineyards being planted close to a body of water?

[a]

The body of water:

Reflects the sun’s rays;
Provides source for irrigation;
Reduces risk of ground frost;
Can provide morning mists to encourage development of noble rot

[q] What are the advantages of a vineyard being planted close to a forest?

[a]

The trees can act as a windbreak, store heat in cold weather, and reduce erosion.

However, forests can also harbor flocks of birds, which are pests

[q]

Temperature directly affects the yield of a vineyard by influencing:

[a]

[q]

Temperature directly affects the quality of a vineyard by influencing:

[a]

Yield level;
Accumulation of sugars and the reduction of acidity in the berry;
Development of wine aromas

[q] What is something a winegrower can do in a cool climate to increase the rate of photosynthesis?

[a] Increase the amount of leaf area and canopy to compensate for slowed photosynthesis

[q] List 5 major soil types

[a]  

Limestone
Chalk (lower density than limestone, so more free draining)
Slate
Granite
Volcanic

[q] Why aren’t vines often planted as seeds?

[a]

Propagation from cuttings is quicker and easier;

plus, propogation allows for grafting onto phylloxera-resistant rootstock
Vines grown through seeds are not genetically identical to the parent vines and although they can show similar characteristics to their parents, more often they are notably different

[q] Grafting used to be done by hand (also known as ____ technique) but now is almost always done by machine (also known as ____ technique).

[a]

hand: whip
machine: omega

[q] What can you add to soil to improve soil structure?

[a]

Gypsum – it improves permeability and aeration

[q] What is the most important aspect of winter pruning?

[a]

Winter pruning dictates the number and location of buds that will form shoots in the next growing season.

Heavily pruned vines will grow fewer shoots the following summer (and so grow fewer leaves)

[q] What does the term ‘vine vigor’ refer to?

[a] It refers to the general growth of the vine, and a vine’s vigor has ramifications on the yield and ripening of the grapes

[q] What are three factors that influence a vine’s vigor?

[a] Available resources for the vine (water, nutrients, temperature);
The vine’s variety, clone, and rootstock;
Whether disease lives in the vineyard where the vine is planted, which can lower vigor

[q] What are three things that can cause excessively low vigor, and what is the solution for each?

[a]

Drought stress –> solved by irrigation (where allowed);
Low soil fertility –> solved by increased fertilization and drainage;
Disease –> solved by diagnosis and treatment

[q] Chlorosis, yellowing of the foliage, is caused by what?

[a]

A deficiency of iron, nitrogen, magnesium, and/or sulfur

[q] Chemical weed control (herbicides) can be organized into three groups:

[a]

Pre-emergence herbicides;
Contact herbicides;
Systemic herbicides

[q]

Pre-emergence herbicides:

Where and when are they best applied?
How are they absorbed?
What do they inhibit?

[a]

Best applied to surface soil before weeds grow;
Absorbed through the roots;
Inhibit the germination of seedlings

[q]

Contact herbicides:

To what are they applied?
What do they destroy?

[a]

Sprayed onto established weeds;
Destroy only the parts that are sprayed

[q]

Systemic herbicides:

What are they sprayed onto?
How are they absorbed?
What do they destroy?

[a]

Sprayed onto established weeds;
Absorbed by the leaves and translocate in the sap (move upward and downward in the plant);
These destroy the whole plant

[q]

How can wind damage be mitigated?

[a]

Artificial Wind Breaks – mobile structures that provide instant protection. Expensive and will need to be replaced;
Natural Wind Breaks – must be planted before vineyard is planted and established, e.g. trees with dense foliage. Trees can harbor pests and disease, and may need pruning and other maintenance.
For maximum effect the crop should be within 10x the height of the break

[q] What is lutte raisonée (aka integrated viticulture, or integrated pest management)?

[a]

Synthetic agrochemicals are permitted but only when there is a clear need;
Vineyards must be constantly monitored for pests and disease;
Complete list of fertilizers, pesticides, and cultural practices are submitted and grower is inspected at least once per year

[q] Are biodynamic growers permitted to use Bordeaux mixture and/or sulfur?

[a]

Yes, biodynamic growers are permitted to use Bordeaux mixture and/or sulfur.

Bordeaux mixture: 3 kg/ha

Sulfur: 7 kg/ha

Sometimes dynamized ashes of target pests are sprayed onto the foliage in an attempt to control the pest

[q] What are the main sugars found in grapes?

[a]

Glucose and fructose, both metabolized by yeast

[q] Fructose is found in what kind of grapes?

[a]

Late harvested. Fructose is more difficult to ferment

[q]

What happens if you have high concentrations of pectins in your grape juice?

How do you handle it?

[a]

Pectins make it difficult to extract and/or clarify grape juice (many aromatic varieties are high in pectins, e.g. Gewürztraminer and Viognier).

Remedy this by adding pectolytic enzymes during grape processing

[q] What are phenolic compounds?

[a]

A group of chemical compounds that affect a wine’s color, texture, astringency and bitterness.

Smaller phenolic molecules (catechins and epicatechins) can taste bitter or waxy, or develop bitter tastes with oxidation

[q]

Are anthocyanins phenolic compounds?

What are anthocyanins responsible for?

[a]

Yes, anthocyanins are phenolic compounds.

They are responsible for red wine color, and are found in the skins

[q]

Are tannins phenolic compounds?

What are tannins responsible for?

[a]

Yes, tannins are phenolic compounds.

They are responsible for astringency and contribute to the weight and body of the wine.

(They are also antioxidants and preservatives)

[q] What is the difference between aspect and slope?

[a]

Slope is the angle of incline of the terrain.

Aspect is the direction the slope faces (east facing, west facing). Aspect relates to the degree of solar exposure

[q]  
Even though grapevines are drought resistant, they still require __-__ inches of rain per year

[a]

20-30 inches

[q] Approximately how many hours of sunlight does a vine require during the growing season?

[a] 1300 hours

[q]

High soil pH (limestone-rich) contributes to higher ____ in grapes.

Low soil pH (acidic soils) can be a deterrent to viticulture. This can be countered by adding ____ to your soil.

[a]

High soil pH (limestone-rich) contributes to higher acidity (low pH) in grapes.

Low soil pH (acidic soils) can be a deterrent to viticulture. This can be countered by adding lime to your soil

[q] What are the four most important North American vine species?

[a]

Vitis berlandieri
Vitis labrusca
Vitis riparia
Vitis rupestris

[q] What are the four anatomical structures of the vine?

[a]

Main shoots;
One-year-old wood;
Permanent wood;
Roots

[q] What are the parts that collectively make up the canopy?

[a]

Stem;
Buds;
Leaves;
Lateral shoots;
Tendrils;
Inflorescences/grape bunches.
These are all structures of the main shoots

[q] In the spring, the main shoots of a vine grow from ____ retained from the previous year

[a]

[q] What role does a vine’s stem have in regards to how a vine functions?

[a]

Transports water and solutes to and from the various vine structures;
Stores carbohydrates

[q] What are solutes?

[a]

In regards to viticulture, they are sugars and minerals – substances that dissolve in liquid to form a solution

[q] What is the difference between a node and an internode?

[a]

Node

The swelling on the stem where other structures of the vine are attached.
Internode

the area, or distance, between nodes.
Fun Fact: The distance between nodes is an indicator of the rate of shoot growth, so internode length varies along the cane corresponding to varying growth rates during the season

[q] What does it mean when shoots lignify?

[a]

When green shoots turn brown, and become woody and rigid.

Once this happens, that shoot is now referred to as a cane

[q] Where do buds form on the vine?

[a] Between the leaf stalk (petiole) and the stem

[q] What are buds made of (read: what do they become)?

[a]

Buds become all the green parts of the vine:

Stem;
Buds;
Tendrils;
Leaves;
Inflorescences

[q] What are the two main types of buds?

[a]

Compound buds (also known as latent buds);
Prompt buds

[q] What is the main difference between compound buds and prompt buds?

[a]

Compound buds form in one growing season and break open in the next growing season;

Prompt buds form and break open in the same growing season

[q]

What do compound buds produce?

Briefly describe what is inside a compound bud

[a]

Compound buds produce the main shoots in the next growing season.

Inside a compound bud there is a primary bud (the main growing point) and smaller secondary and tertiary buds; the latter buds usually only grow if the primary bud has suffered damage (e.g. spring frost)

[q] What do prompt buds produce?

[a] Lateral shoots

[q] On what do prompt buds grow?

[a] They grow on the main shoot which had just grown from a compound bud

[q]

Lateral shoots grow from buds formed in the:

Current year
Previous year

[a]

Current year (because they grow from Prompt buds)

[q]

Compared to main shoots, lateral shoots are:

smaller and thinner
larger and thicker
the same size

[a] Smaller and thinner

[q] What structures do lateral shoots have?

[a]

Stem;
Leaves;
Buds;
Tendrils;
Sometimes inflorescences

[q] What is the main function of lateral shoots?

[a]

To allow the vine to continue growing if the tip of the main shoot has been damaged or eaten; they’re especially helpful being an additional source of photosynthesis

[q] Why is it undesirable to have lateral shoots near the base of the main shoot?

[a]

They can impede air flow and shade the fruit too much.

They’re usually removed during summer pruning

[q]

What are the Pros of keeping the inflorescences on lateral shoots and letting them develop into clusters (also known as a ‘second crop’)?

[a]

If they are green harvested, their removal is thought to improve the ripening process and enhance the uniformity of ripeness of the remaining bunches;
If they are hand-harvested, the vineyard manager can be selective and either give them a longer hang time or, if they are harvested, the clusters can be separated

[q]

What is the profile of bunches from a ‘second crop’ harvested at the same time as the main crop?

[a]

Higher in acidity;
Lower in potential alcohol;
Potentially unripe tannins, aromas, and flavors;
In black grapes, the bunches will have less color development

[q] What role do the tendrils have?

[a] Provide support for the vine;
Help position the vine canopy;
Help keep canopy in place

[q] What are stomata?

[a]

Stomata are pores on the underside of leaves that allow a plant to take in carbon dioxide, which is needed for photosynthesis;

They also allow water vapor to diffuse out of the plant, but when conditions are hot or dry they can close to reduce water loss, but limits photosynthesis by preventing carbon dioxide from entering the vine

[q] Where in the vine does photosynthesis mainly happen?

[a] In the leaves

[q] What is inflorescence?

[a] A cluster of flowers on a stem which, when fertilized, develops into a bunch of grapes at fruit set

[q] How many inflorescences develop on each main shoot?

[a] Between 1 and 3

[q] What are the three main parts of a grape?

[a]

Pulp
Skin
Seeds

[q] What is a teinturier grape variety?

[a] One that has red-colored pulp, as opposed to the majority of grape pulp which is colorless

[q] What does grape pulp consist of?

[a]

Water
Sugars
Acids
Some aroma compounds and aroma precursors

[q] What does grape skin consist of?

[a]

High concentrations of aroma compounds and aroma precursors
Tannins
Color compounds

[q] What do seeds consist of?

[a]

Oils
Tannins
The embryo, which can grow into a new plant

[q] As seeds mature, their color goes from ___ to ___.

[a] Yellow to dark brown

[q] What is the powdery, waxy coating on grapes called?

[a] Bloom

[q] What does ‘one-year-old wood’ refer to?

[a] The main shoots from the last growing season that were kept at pruning

[q] What is the most important function of one-year old wood?

[a] It has the compound buds that will release the main shoots for the upcoming growing season

[q] One-year-old wood will either be called a ___ or a ___, depending on how the vine was pruned.

[a]

A cane or a spur

[q]

Any of the woody parts of the vine, including the trunk, that are older than one year are called ___ ___.

[a] Permanent wood

[q] What are cordons?

[a]

Horizontal “arms” of a vine made of permanent wood

[q] What functions do the roots of a vine have?

[a]

Anchor the vine to the soil
Uptake water and nutrients
Store carbohydrates
Produce hormones for growth and ripening

[q]

Most of a vine’s roots are found:

In the top 25 cm of the soil
In the top 50 cm of the soil
In the top 100 cm of the soil

[a] In the top 50 cm of the soil

[q] How are vines propogated in today’s viticulture?

[a] By cuttings or layering

[q] What is a cutting?

[a] A section of a vine shoot that is planted which then grows as a new plant

[q] What is layering and how is it done?

[a]

Using a shoot from an established, neighboring vine to produce a new vine.

The shoot is bent down and a section of it is buried in the ground with the tip of it pointing up out of the ground. The buried part of the shoot takes root. Once the new roots are established, the cane linking the new growth to the original plant is cut.

The new vine now grows on its own roots, not those of a rootstock, which can be problematic in that the new roots don’t offer any kind of resistance to phylloxera

[q] Why is layering done?

[a]

To fill in gaps in the vineyard, like when a vine is pulled or dies

[q]

Cutting and layering generally produce vines that are:

genetically identical to
completely different from
the parent vine

[a] Genetically identical

[q] During plant growth, random mutations in the genetic code of a vine create _____.

[a] Clones

[q] What is clonal selection?

[a]

When vine nurseries or grape growers propagate a vine that has somewhat different but desirable characteristics, or mutations, by using cuttings from that vine to grow new vines which will then have the same desirable and somewhat different characteristics (mutations).

Some clones have mutations such as higher yields, bigger or smaller grapes, and varying tannin levels, all of which can be applied to the needs of the grape grower and what style of wine they want to produce

[q] Why would a grape grower plant a number of different clones of the same grape variety rather than planting vines that are all the same clone?

[a]

To increase diversity in the vineyard;
To make the vineyard less susceptible to disease

[q] What is Mass Selection (also known as Sélection Massale)?

[a] What is Mass Selection (also known as Sélection Massale)?

[q] For what style of Port is Malvasia generally a large part of the blend?

[a]

A term used to describe a traditional method of vineyard propagation.

Grape growers make a selection of particular vines within an old vineyard, and use this subset as the genetic stock to plant a new vineyard.

The vines selected for propagation have attributes which are important to the producer, whether that be yield, hardiness or sensory qualities.

[q] What is a major downside of Mass Selection?

[a] If the parent vine carries any disease, that disease will be passed down to the new vines through its cuttings, increasing the spread of the disease

[q] Describe the difference between Mass Selection and Clonal Selection

[a]

Clonal selection and mass selection are often confusing. Simply put, mass selection is the old way – done ‘at home’ in the vineyard – and clonal selection is done deliberately at a grapevine nursery. Both methods have their supporters and opponents, but many believe that massale selection preserves more diversity in the vineyard.

With mass selection a grower selects the vines from their vineyards that exhibit more desirable attributes and they use cuttings from these to plant new vines. So while these selected vines produce the finest fruit they are not necessarily totally identical.

Clonal selection takes mass selection to a deeper level, where better vines are selected for propagation again and again until there is a more precise vine that can be replicated at the nursery, be officially recognized, registered and made available for sale from the nursery. Clones are identical to their parent. The idea of clonal selection is to have an army of the same vine showing the same characteristic(s)

[q]

Generally, new grape varieties are typically produced from:

Roots
Seeds
Cuttings

[a] Seeds

[q]

What are the steps a grape grower would take to create a new grape variety?

[a]

Cross fertilize two vines;
pollen from the flowers of one vine is transferred to the stigmas of the flowers of another vine;
Plant the seeds from this new plant and grow new vines;
These new vines that grow from the seeds will all have different characteristics, and if one of the new vines has desirable characteristics it may be propagated by cuttings to create identical vines

[q] What is the difference between and cross and a hybrid?

[a]

A cross is a plant offspring that has two parent vines from the same species.

A hybrid is a plant offspring that has two parent vines from different species

[q] What are the differing aims of creating and breeding crosses and hybrids?

[a]

The aim of creating and breeding a cross is usually to create an offspring that has favorable characteristics of the two parent vines;

The aim of creating and breeding a hybrid is usually to create an offspring that combines the resistance of non-vinifera species (to diseases, pests or climatic extremes) and the quality of fruit from V. vinifera

[q] When does budburst (also known as budbreak) occur in the Northern and Southern Hemispheres?

[a]

Northern Hemisphere: March – April

Southern Hemisphere: September – October

Budbreak marks the end of winter dormancy

[q] What does the timing of budburst depend on?

[a]

Air temperature;
Soil temperature;
Grape variety;
Human factors

[q]

What are the buds that are bursting during budbreak (prompt buds or compound buds)?

What air temperature do they need to burst?

[a]

Budbreak buds are the compound buds formed in the previous year’s growing season;
The buds need a sustained average air temperature of ~10°C / 50°F

[q] Why do regions that have a marked contrast in their seasonal temperatures (e.g. Continental climate) typically have a greater advantage of homogenous budbreak and subsequent growing phases, and even ripening over regions that have less contrast in their seasonal temperatures (e.g. Maritime climate)?

[a] Rapidly increasing temperatures in the spring mean that the vines benefit from the rise in temperature and are in sync with each other development-wise, whereas a region that has less contrast between winter and spring temperatures can be confusing for the vines, particularly when there are mild days during winter when the vine is supposed to be dormant. This can lead to uneven budburst, and if there’s a frost, uneven yields

[q]

Higher soil temperatures around the roots encourage budburst to happen:

Earlier
Later

[a]

Earlier

Dry, well-draining soils (e.g. sandy soils) tend to warm up more quickly than water-storing soils (e.g. clay-rich soils)

[q]

Grape varieties that require relatively low temperatures at budburst are referred to as:

‘early budding’
‘early ripening’
‘early rising’

[a]

‘Early budding’

e.g. Chardonnay, Pinot Noir

[q]

Grape varieties that require higher temperatures are referred to as:

‘late budding’
‘late ripening’
‘late rising’

[a]

[q]

If vines are winter pruned late in the dormancy period, what can this do to budbreak?

Encourage budbreak
Postpone budbreak
It doesn’t affect budbreak

[a]

Postpone budbreak

This technique can be used in areas where spring frost is known to be a problem

[q]

When do vines have shoot and leaf growth in the Northern and Southern Hemispheres?

[a]

Northern Hemisphere: March – July

Southern Hemisphere: September–January

[q] The fastest rate of vine growth generally occurs:

Between budburst and flowering

Between flowering and fruit set

Around véraison

[a] Between budburst and flowering

[q] What drives initial shoot growth?

[a] Carbohydrates stored in the vine’s roots, trunk and branches

[q] What stimulates further shoot, leaf, and vine growth?

[a] Photosynthesis, which increases with leaf development

Remember: the vine needs adequate warmth and sunlight to photosynthesize

[q] What are the principal nutrients a vine needs to grow?

[a] Nitrogen;

Potassium;

Phosphorus

[q] What are some consequences if a vine experiences stunted shoot growth (which can happen from dry soils, poor nutrient availability, or water stress)?

[a] Small, weak shoots;

Reduction in leaf number or smaller leaves;

Inflorescences that don’t flower properly;

Grape bunches that do not ripen fully.

this can lead to poor fruit quality and lower yields

[q] When is flowering and fruit set in the Northern and Southern Hemispheres?

[a]

Northern Hemisphere: May–June

Southern Hemisphere: November–December

[q] What are some conditions in the present growing season that can limit bud fruitfulness for the next growing season?

[a] Shading of compound buds;

Low temperatures (under 25°C / 77°F);

Water stress;

Nutrient deficiency

[q] The yield and quality of grapes in the current growing season are strongly influenced by:

Flowering and fruit set

Harvest date

Aspect of the vineyard

[a] Flowering and fruit set

[q] In pollination, pollen grains are shed from the ____ and land on the moistened ____ surface.

[a] Shed from the stamen (or anther) and land on the stigma surface

[q] Flowering typically takes place within:

8 hours

8 weeks

18 weeks

weeks of budburst

[a] 8 weeks

[q] Fruit set is the term used to describe the transition from ____ to ____.

[a] Flower to grape

[q] For successful flowering, temperatures must be warm (~17°C / 63°F).

What happens if there are low temperatures during flowering?

[a] The duration of flowering is lengthened;

The consequence of which is a negative effect on the evenness of ripening

[q] Typically, what percent of flowers become grapes?

[a] 30% (it can range from 0-60%)

[q] The two common forms of irregular fruit set are:

[a] Coulure

Millerandage

[q] What is coulure, and what causes it?

[a]

A

A high proportion of poor fruit set in grape bunch (unsuccessful fertilization).

Coulure is caused by an imbalance in carbohydrate levels, and that imbalance can be caused by:

low photosynthesis (cloudy conditions);

water stress;

improper canopy management;

overly-fertile soil

[q] Millerandage:

What is it?

What causes it?

[a] It’s when a high percentage of grapes within a bunch are seedless and, usually, smaller than the normal berries with properly formed seeds;

these smaller grapes can either ripen normally or stay unripe, which can affect the quality of the crop;

Caused by unfavorable weather (cold, wet, windy) at fruit set

[q] When does grape development occur in the Northern and Southern Hemispheres?

[a] Northern Hemisphere: June–October

Southern Hemisphere: December–April

[q] What are the four stages of grape development?

Which stage is the most important in determining final grape quality?

[a] Berry formation

Véraison

Ripening

Extra-Ripening

[q] Berry formation starts soon after:

Flowering

Fruit set

Harvest

[a] Fruit set

[q] What is happening inside the grape during berry formation?

[a] Accumulation of tartaric and malic acids;

Accumulation of tannins;

Development of aroma compounds and aroma precursors;

High water flow into the grape;

Low sugar levels

[q] What does the vine need during berry formation?

[a] Sunlight

Warmth

Mild water stress

[q] What happens if a vine gets too much water and nutrients during the berry formation stage?

[a] Shoot growth is encouraged over grape ripening, which delays the onset of the ripening stage which means that the grapes might not ripen fully in time for harvest

[q] Grape varieties with tight bunches, such as Sémillon and Pinot Noir, can be prone to fungal disease. Why?

[a] The possibility of their grape skins splitting during the growth cycle is increased due to the very nature of their tight, compact bunches;

Lack of air flow in the crowded bunches increases humidity, and if the skins split then disease is difficult to avoid

[q] What is véraison?

[a] When grape berries change color signaling the onset of final ripening.

White grapes go from green to yellow, and red grapes go from green to red

[q] What’s happening inside the grape during the ripening stage?

[a] Cells in the grape expand rapidly

Sugar and water accumulate

Acid levels fall

Tannins, color, aroma precursors and aroma compounds develop 

[q] How can excessively cloudy or excessively hot and dry conditions affect the ripening stage?

[a] If cloudy conditions, photosynthesis slows and can interfere with sugar accumulation (read: lead to under-ripe grapes);

If hot and dry conditions, photosynthesis slows or can even stop, also interfering with sugar accumulation

[q] In warm, dry conditions grape transpiration (and sugar accumulation) is:

faster than in cool, humid conditions

slower than in cool, humid conditions

grape transpiration and sugar accumulation never fluctuate

[a] Faster than in cool, humid conditions

[q] What is respiration?

[a] Vines produces energy by combining sugars (from photosynthesis), oxygen, and other compounds with water and carbon dioxide.

During respiration, that energy stored by the vine is released

[q] Why do wines from cooler climates tend to have higher natural acidity?

[a] Because malic acid is used in respiration during the ripening stage, and respiration is slower at cool temperatures than warm ones.

This is also why cooler nighttime temperatures are important for producing balanced grapes with fresh acidity

[q] During the ripening stage in a normal year, which compound levels increase and which compound levels decrease in the grapes?

[a] Increase:

Aroma compounds and aroma precursors

Anthocyanins

Decrease:

Methoxypyrazine

Tannins (they polymerize)

[q] What are the two biggest differentiators in how grapes ripen during the ripening stage?

[a] Heat

Sunlight

[q] What are four factors that determine the length of the ripening stage?

[a] Grape variety

Climatic conditions

Vine and vineyard management

Time of harvest

[q] What happens inside the grape during the extra-ripening stage?

[a] Sugars accumulate (and water is lost) from grape transpiration

[x] GOOD JOB!! [restart] Return to page view

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