Chapter 7 - Canopy Management Flashcards
The aims of canopy management:
Maximize light interception
Reduce shading
Reduce moisture - increase air circulation in the canopy
Ensure microclimate for the grapes is uniform so the grapes ripen evenly
Promote balance of vegetative and reproductive functions
Ease mechanization and/or manual labor
Budfruitfulness
The number of inflorescences that will develop from.a bud
Shady conditons is associated with reduced bud fruitfulness and therefore the bud producing more vegetative structures than inflorescences
What is vine balance (bt vegetative and reproductive functions) based on?
Growing environment Varietal Rootstock Presence of disease Age of vine Style of wine being produced (quality, rose?)
Balanced Cycle
- Light - stimulates bud break, bunch initiation, fruit set berry growth, increase bud fruitfulness
- Fruit Weight - per shoot is increased
- Shoot Growth - depressed because there’s more fruit growth
- Canopy Density - decreased because there is less leaf area
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Vegetative Cycle (under-cropping)
- Shade - depresses bud break, bunch initiation, fruit set, berry growth, bud fruitfulness
- Fruit Weight - decreases per shoot
- Shoot Growth - increases because less fruit growth (less competition for sugars)
- Canopy Density - increases bc more leaf area
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Over-cropping
When fruit yield is too high
Can take away sugars meant for carbohydrage storage for teh winter. Can weaken the vine in the following year
Winter pruning is vital for vine balance. Why?
These decisions will influence the number of shoots and potential yield in the upcoming growing season
What is yield dependent on?
The yield per vine and the planting density
What are the canopy management techniques?
Vine training Winter pruning Vine trellising Overall plant vigor management Summer pruning
What is optimal vine density influenced by?
Vigor of the vine
Type of trellising system
Waht access is needed between the vines (machinery?)
You generally want to plant your vineyards north to south so there’s even sunlight exposure (but with more shading on the west side of the canopy)
What factors determine the training and trellising method used?
vigor of the vine
Topography of the land - steep slopes? Windy site?
Need for mechanization
Vine Training
Head trained - no permanent arm
Cordon trained
Vine pruning - 2 methods
Spur pruned - one year old wood is cut back to 2-3 buds
Replacement cane pruned - one year old wood with 8-20 buds
Generally would not do cordon trained, replacement cane pruned
Untrellised vineyards
What are the pros/cons
Head trained, spur pruned vines - Bush vines
Pros:
Good for dry, hot climates bc it provides extra shading and prevents grapes from becoming sunburned
Easy/inexpensive to develop
Cons:
Cannot be mechanized
Only suitable for low vigor vines - canopy would become too dense
Not suitable for wet conditions - too much humidity, not enough air circulation
Trellisted vineyards
What are the pros/cons
VSP
Complex training systems
Pro: Good for high vigor vines Allows for mechanization Increases air flow Maximizes light inerception
Con:
Expensive
Needs maintaining
What is VSP
Shoots are trained vertically in a single narrow canopy
Good for low to moderate vigor vines
What is Guyot training
Head trained/ replacement cane pruned VSP
Complex Training Systems
Splits the canopy to reduce shade and maximize sunlight
Used for high vigor vines
More difficult to manage and mechanize than VSP
Complex training systems split horizontally
Geneval Double Curtain
Lyre
Complex training system split vertically
Smart-Dyson
Scott-Henry
What are the 2 summer pruning techniques that can’t be mechanized?
Pinching
Disbudding
Summer pruning techniques
Disbudding Shoot removal Shoot positioning Pinching Shoot trimming Leaf Removal Greem harvesting
Describe disbudding
Removal of buds the manage vine balance and remove buds that are poorly positioned
Growers will often leave extra buds on during winter pruning in case buds get damaged like by spring frost
Debudding in spring will help bring the vine into balance and remove ones that are poorly positioned (ie ones that are too close together)
Why remove shoots?
Often laterals
Generally remove the ones that are infertile or poorly positioned (too close togehter)
Want an open canopy
Pinching defn
Removes the shoot tips at flowering to improve fruit set
Green harvesting
Unripe grapes are removed so the rest can ripen
If done near veraison, will enhance ripening of the remaining grapes
