Ch 6. Vineyard Management

Question 1

What must a producer take into account when selecting a potential site for a vineyard?

Answer 1

1. Environmental/climate;
2. Business considerations;
3. Grape variety

Question 2

Which environmental/climate conditions?
Why are these important?

Answer 2

*Av. Sunlight/rainfall and temp.
* Fertility of soil and drainage

These influence choice of grape, density of planting and training and trellising selection

Question 3

Which business considerations are relevant?

Answer 3

• Proximity to infrastructure and utilities;
• availabilty of workforce;
• accessibility for machinery;
• cost of land and financial viability.

Question 4

Why is grape variety relevant to the decision?

Answer 4

• It must be capable of being grown successfully in the climatic and environmental conditions;
• there should be a market for the grape/ wine;
• legal restrictions may apply to the varieties which can be used.

Question 5

When are vines normally replaced?

Answer 5

Between 30 - 50 years of age

Question 6

1. What are the main techniques used to manage the vine?
2. What influences the choices made?

Answer 6

1. Training, pruning, trellising and plant density.
2. The vineyard resources i.e. temperature, sunlight, rainfall and soil nutrients.
3. Will machine harvesting be used.

Question 7

What are two main types of training?

Answer 7

1. Head training;
2. Cordon training.

Question 8

Describe head training? How is it pruned?

Answer 8

Relatively little permanent wood normally a trunk only and may be short armsof permanent wood.
May be spur- or replacement cane pruned.

Question 9

Describe Cordon training.
What is an advantage of this approach?

Answer 9

Typically a trunk with one or more permanent horizontal arms ( cordons).
Usually spur-trained.

This method allows for machine harvesting due to the sturdy cordon.

Question 10

What is pruning? Why is it done? When is it done?

Answer 10

Pruning is the removal of unwanted leaves, canes and permanent wood.
It shapes the vine and limits it’s size.
It is normally done in summer and winter.

Question 11

What is main purpose of winter pruning?

Answer 11

To determine the number and location of buds that will form shoots in the following season. It is important that they are not too close together which helps canopy management ( which is part of summer pruning).

Question 12

What are two styles of winter pruning?

Answer 12

Spur pruning and Replacement cane pruning.

Question 13

Describe spur pruning.

Answer 13

Spurs are short sections of 1yr old wood cut to have only 2/3 buds. Distributed along a cordon of permanent wood ( cordon training ) or around the top of the trunk (head training).

Question 14

Describe replacement cane pruning.

Answer 14

Long sections of 1 yr old wood with 8 to 20 buds. Typically one cane ( single Guyot) or two canes ( double Guyot) retained and tied to trellis for support. Normally seen on head trained vines. Requires skilled workers to identify best canes - more expensive.

Question 15

What is purpose of summer pruning.

Answer 15

Canopy management to restrict excess vegetative growth. Directs glucose to grapes. Also used to strip leaves for sunlight exposure.

Question 16

What is canopy?

Answer 16

All of vines green parts.

Question 17

What is important choice for growers on canopy management?

Answer 17

Trellis or not.

Question 18

What is a trellis?

Answer 18

Permanent structure of stakes and wires to support replacement canes (head trained) and annual growth eg on cordon trained.

Question 19

What is an untrellised vine normally called? How is it trained and pruned?

Answer 19

Bush vine - shoots will hang down to ground. Normally head trained and spur pruned.

Question 20

Why might a grower choose to grow bush vines?

Answer 20

To protect grapes with extra shade in warm or hot, dry sunny regions eg Barossa, Jerez, S. Rhone.

Question 21

Why might bush vines not be suitable in cool or wet regions?

Answer 21

Shade can impede grape ripening and lack of airflow can promote disease.

Question 22

Whatis this training system sometimes known as?

Answer 22

Gobelet

Question 23

Are untrellised vines suitable for machine harvesting?

Answer 23

No.

Question 24

What is trellising used for?

Answer 24

The vines canes and shoots are tied to horizontal wires on the trellis. This is known as canopy management.

Question 25

What are reasons for using trellising?

Answer 25

1. Mechanical harvesting is simplified and spraying is more effective; 2. In low sunlight areas ripening can be maximised by having an open canopy; 3. In areas with intense sunlight, shading can be created to avoid sunburn; 4. An open canopy encourages airflow to reduce fungal disease risk, particularly in wet areas.

Question 26

What is VSP.

Answer 26

Vertical Shoot Positioning. Shoots are trained vertically and tied onto trellis forming a narrow single canopy. This canopy open, aerated and as shade free as possible.

Question 27

How can VSP be adapted in sunny regions?

Answer 27

Tops of shoots are not tied in and flop over creating some shade. An alternative to bush which allows mechanical harvesting.

Question 28

What is planting density and how might it be measured?

Answer 28

Number of vines planted in a given area. Measured as number of vines per hectare/ acre.

Question 29

What factors influence density? ( as set out in text)

Answer 29

Water and nutrient availability.

Question 30

In an area with limited water availability what density might be appropriate?

Answer 30

Low ensity as it reduces competition for scarce water with other vine roots.

Question 31

In an area with sufficient rainfall/ water availability and low nutrients what density might be appropriate?

Answer 31

Vines thrive in less fertile soil provided they have enough water. In areas with water sufficiency high density planting will mean competition for this andrestrictexcessive vegetative growth i.e. green.

Question 32

How important is it to have the correct number of buds after winter pruning?

Answer 32

The vine stores energy (carbohydrates) in winter. Too few buds then they get access to too much energyand will grow vigorously. Too many buds then theywont have enough energy and vine will struggleto ripen its crop load.

Question 33

In an area with sufficient rainfall/ water availability and high level of nutrients what density might be appropriate?

Answer 33

In some New World vineyards they use low density with multiple cordons or canes.

Question 34

What is yield? How is it usually measured?

Answer 34

Yield is a measure ofthe amount of grapes produced. It is may be measured as weight- tonnes of grapes per hectare,or volume - hectolitres of wine per hectare.

Question 35

Why must a producer know predicted yield?

Answer 35

1. Legal reqts; 2. Contractual obligations; 3. Capacity at the winery.

Question 36

How might yield bepredicted? What makes it uncertain?

Answer 36

The number of buds left on the vine after winter pruning. Uncertainty is caused by loss due frost damage, poor fruit set and pests and diseases.

Question 37

How can high yield be managed?

Answer 37

By removing immature grapes using green harvesting after veraison. Its needsto be done becorrectly or the grape will compensate with larger grapes in retained grapes. This can dilute flavours.