Canopy Management

Question 1

What are the key aims of canopy managment?

Answer 1

Increase sunlight- photosynthesis and better for polymerisation of tannins and anthocyanins
Increase airflow- disease
Ease of mintenence and harvesting in vy.
Reduce shade
Ensure microclimate for grapes as uniform as possible= grapes ripen easily

Question 2

What are the effects of promoting sunlight?

Answer 2

More sugar- greater photosynthesis
Increased tannins- better polymerisation and less bitterness
Enhances anthocyanins
Decreased malic acid
More aroma ps & cs (terpenes)
Decreased methoxypyrazines

Question 3

What is under cropping and the effects to the vine?

Answer 3

When the fruit yield for the vine is too low.
-shoot growth continues, not much fruit to ripen
-shoots and leaves compete with grapes for sugar= uneven ripening
-dense shadowy canopy- lack of sunlight= lower fruit quality
Lower yields next year= reduced bud fruitfulness
Lower yields= under cropping- ‘vegetative cycle’

Question 4

What is over cropping and what are the effects to the vine?

Answer 4

If fruit is too high compared to the vigour of the vine
-gains sugars from carbs in carbs, trunk, cordons, roots
-vine needs these in winter and spring- weakens the vine

Question 5

What are the canopy management techniques?

Answer 5

summer pruning
-debudding
-pinching
-shoot positioning
-shoot trimming
-leaf removal
-crop thinning/green harvesting
trellising
training
winter pruning
Overall plant vigour management
-nitrogen fertilisation
-irrigation
-cover cropping

Question 6

In terms of row orientation, which direct gets the most even sun exposure?

Answer 6

Noth-south

Question 7

In terms of row orientation, which direction is exposed to the afternoon sun and therefore needs more shading?

Answer 7

West

Question 8

In terms of row orientation, how can the grape grower help against prevailing winds?

Answer 8

Planting the vineyard at a 90 degree angle to the direction of the wine

Question 9

What does the vine training, pruning and trellising depends on?

Answer 9

1. Vine vigour- natural (temp, water, nutrients, grape variety, clone, rootstock) and any disease)
   Human- RDI, low vigour rootstocks)
2. Topography- steep slopes/windy sites. eg N Rhone/Mosel- individual stakes, not wired trellis
3. Need for mechanisation- VSP/bush vines

Question 10

What is head training?

Answer 10

Have little perm wood, usually from trunk, v short stubs growing from top of trunk
Spur/replacement cane pruned

Question 11

What is cordon training?

Answer 11

Trunk and one or more perm horizontal arms of perm wood- cordons
Spur pruned

Question 12

What is spur pruning?

Answer 12

-Spurs= short section of one year old wood (shoots from last years growing season that have been lignified)
-Buds cut back to only 2 or 3
-Distributed along cordon (cordon training) or around head (head training)

Question 13

What is replacement cane pruning?

Answer 13

-Canes= longer sections of one year old wood.
-8-20 buds.
-More complex than spur pruning- requires skilled labour force to select suitable canes and train them
- Number of buds left on the vine depend on vigour of the vine=more buds= more vigorous vines= influences balance of the vine
-Calculate balance and whether or not more/less buds need to be retained. Calculate yield and weight of pruning cuttings in dormant season.

Question 14

What is untrellised vineyards?

Answer 14

Head trained, spur pruned= bush vines
Easy and cheap to develop
Shoots may droop down= shade for grapes
Hot and sunny regions- La Mancha= no sunburn

Question 15

What are the disadvantages of untrellised vineyards?

Answer 15

Not suitable for mechanisation

Question 16

Where are untrellised vineyards most suited to?

Answer 16

Dry regions= not too much canopy
If too much vigour= too much canopy= disease and shade fruit too much.

Question 17

What is vertical shoot postitioning?

Answer 17

Shoots of the vine are trained upwards to receive the maximum amount of sunlight and to increase airflow- reduces risk of disease.
Head trained, replacement cane trained, spur pruned.
Best suited to vines with low/med vigour

Question 18

Why would one use complex training systems?

Answer 18

If high vigour vines- split the canopy= reduce shade and maximise sunlight interception

Question 19

Give an example of training systems that splits horizontally

Answer 19

Geneva Double Curtain
Lyre

Question 20

Give an example of training systems that splits vertically

Answer 20

Scott-Henry

Question 21

What does disbudding do?

Answer 21

-Reduces buds for competition of sugar and nutrients.
-Manages vine balance and yields
-Removes poorly positioned buds
-Comply with regulations
-Winter- leave high number of buds incase of damage= spring frosts