Canopy Management Techniques

Question 1

What are the six aims of canopy management?

Answer 1

1. maximize the effectiveness of light interception by the vine canopy
2. reduce shade within the canopy
3. ensure that the microclimate for the grapes is as uniform as possible, so that grapes ripen evenly
4. promote balance between the vegetative and reproductive functions of the vine
5. arrange the vine canopy to ease mechanization and/or manual labor
6. promote air circulation through the canopy to reduce incidence of disease

Question 2

What is the purpose of maximizing leaf surface area exposed to sunlight?

Answer 2

• increases the vine’s photosynthetic capacity (compared to a vine with a dense, shaded canopy)
• increases the vine’s ability to ripen larger yields

Question 3

What are the problems associated with dense canopies?

Answer 3

• poor air circulation
• higher humidity within the canopy
• suitable conditions for fungal diseases to develop
• fungicides will have less penetration into the canopy

Question 4

What are the seven effects of good canopy management on grape quality due to increased exposure to sun and heat?

Answer 4

1. increased sugar levels
2. increases tannin levels and riper tannins in grape skins
3. enhanced color in black grape skins
4. decreased malic acid
5. increased levels of favorable aroma precursors
6. decreased methoxypyrazines
7. reduction of fungal disease pressure

Question 5

Define optimal crop load.

Answer 5

The maximum yield of grapes that will allow for the required grape composition for the desired wine style and quality

Question 6

Describe a balanced cycle of canopy management.

Answer 6

After veraison, sugars and other compounds needed for growth are allocated to fruit development, rather than shoot growth.

With less shoot growth, the canopy is less likely to become dense and shaded.

This leads to higher quality fruit and enhanced bud fruitfulness the next year. The balanced cycle continues.

Question 7

Describe a vegetative cycle of canopy management.

Answer 7

Low yields of fruit can lead to high vigor of shoots and leaves.

The shoots and leaves compete for sugar, negatively impacting grape development.

This leads to a dense canopy and lower quality fruit due to shading. This will result in low yields the next year due to reduced bud fruitfulness as the vine enters the vegetative cycle.

Question 8

Define undercropping.

Answer 8

The yield of fruit is too low for the vigor of the vine.

Question 9

Define overcropping.

Answer 9

If the yield of fruit is too high for the vigor of the vine.

Question 10

What are five factors that determine the ideal amount of fruit?

Answer 10

1. climate
2. water and nutrients
3. grape variety
4. choice of rootstock
5. desired wine style

Question 11

At what stage of the annual vineyard activities can the number of shoots on a vine be controlled?

Answer 11

• winter pruning
• summer pruning

Question 12

Define yield.

Answer 12

A measure of the amount of fruit produced. Either presented as weight per vine (kg/vine) or weight per unit of area (tons/hectare).

Question 13

What types of laws exist over yield?

Answer 13

In EU countries, legislation may specify maximum yield per area of land.