VINEYARD CALENDAR Flashcards
Why is leaf pulling early in spring less of a problem than later in the season? (in terms of sunburn)
The young green grapes will protect themselves by creating a kind of ‘sunscreen’. After veraison they will just get sunburned.
What would be a good moment to start the budrubbing
After risk of springfrost (1st week of may in BDX)
What are ‘watershoots’?
Undesirable shoots from latent buds originating from above ground wood.
What is the risk of doing shoot thinning too early or too late? + indication of timing
Early to mid summer
Too early: regrowth
Too late: more difficult to remove
What parameters need to be recorded per vine throughout the year? (7)
- Number of buds
- Number of shoots
- Number of inflorescence
- Number of bunches (at version)
- Number of berries per bunch
- Berry weight
- Average yield
What are the main aims of wire lifting? (3)
- Increasing interception of light by leaves
- Aeration and cluster illumination
- Facilitating passages of tractors
When is the wire lifting being done?
Northern Hemisphere
May 1st, July 2nd
Southern Hemisphere
November 1st, July 2nd
Name 5 aims of summer trimming
- Improve spray coverage
- Reduce susceptibility to disease
- Facilitating passage of tractors
- Carbohydrate partitioning towards inflorescence
- Reducing evaporated transpiration
What would be a reason to start summer trimming or topping early?
Limitation of risk coulure in susceptible varieties
Name 4 types of irrigation
- Flood irrigation
- Over-head irrigation
- Drip irrigation
- Sub-surface irrigation
At which stages in the vine cycle does the wine needs sufficient water the most?
Flowering and veraison
Name an advantage of leaf removal specific for red and one for white
Red: increased synthesis of polyphenols (tannin and anthocyanin)
White: Increased aromatics (thiols)
At what two stages will leaf removal take place? Name early and late
Early: fruitset
Late: near maturity
What is the main disadvantage of machine harvesting in relation to fruit quality
Fruit will be de stemmed, more oxidation, more sulphur needed for protection
Name 3 consequences for a vine with of excess vigour
Increased transpiration
Increased foliar area
Increased risk of diseases
Name 4 principles of canopy management (desired/aim and undesired)
- Desired: large, wel exposed, canopy surface
- Desired: Good leaf/fruit ratio
- Desired: suitable for mechanical practises
- Undesired: shade of adjacent canopies or cluster zone
What are the main factors having effect on photosynthesis in terms of environment? (4)
Sunlight (radiation)
Temperature
Balance atmospheric vapor pressure deficit
Soil water status
In what way do leaves have influence on photosynthesis? (3)
Leaf age
Morphology (primary or secondary)
Location (inside or outside the canopy)
Name 6 summer pruning operations
Bud removal
Shoot removal
Trellising
Hedging
Leaf removal
Grape thinning (green harvest)
Name the three places where shoots can be removed in the summer?
The arm (secondary shoots)
The head of the trunk
The base of the trunk
How often is the shoot lifting being done? And when?
2x
Before and around flowering
What are the objectives of wire/shoot lifting? (3)
Improve microclimate canopy
Improve grapes exposure to light
Making tractor passing easier
What are the objectives of leaf removal? (3)
- Improve sanitary status of the grapes by more grape exposure, air, chemical efficiency
- Change berry composition, tannin, anthocyanin and aroma precursors
- Reduce yield
Is leaf removal more effective early in the season (fruitset) or late in the season (veraison)?
Early
Less risk for bunch rot
Increase and stability of polyphenols
Decrease of IBMP, Increase of floral aromas
What is the risk of late bud removal?
Necrosis & risk of wood disease
Due to large pruning wounds.
Why is it important to be on time with moving the free wires in the trellis system?
Otherwise it will take a lot more time due to lignified tendrils being attached to the wire
How does leaf removal lead to lower yields?
Early exposure of sun to the inflorescence will induce reduction of flowering
Which leaves are removed during leaf removal late in the season, young or old? Why?
Young
Because only young leaves produce sugar at the upper part of the canopy. You want to reduce sugar content.
The earlier you expose grapes to the sun the …
the better they are resistant to sunburn. The thicker the skins, the more polyphenols and anthocyanin
How much gr/l sugar do you need to raise the degree of alcohol with 1%
17 gr/l
