Chapter Four - Viticulture Flashcards
Stages of the annual growth cycle of a vine
- Winter dormancy
- Weeping
- Bud Break
- Shoot & leaf growth
- Photosynthesis
- Flowering
- Berry set
- Veraison
- Phenolic maturity
- Harvest
Translocation
The process by which materials are moved from one part of the vine to another
Photosynthesis
The process by which sunlight is converted into sugar
Transpiration
The process by which water evaporates through openings on the underside of the leaves
Respiration
The process by which sugar is broken down and converted into biological energy
A problem that causes poor fruit set, also known as “shatter”
Coulure
A soil based roundworm that has become more prevalent with the increased use of shallow-rooted rootstock
Nematode
A mold that is sometimes beneficial, also known as “noble rot.”
Botrytis Cinerea
A fungal disease also known as powdery mildew
Oidium
A problem with abnormal fruit set that causes grape bunches to have a high proportion of small, seedless berries mixed in with normal, larger berries
Millerandage
A fungal disease also known as downy mildew
Peronospora
A bacterial disease spread by insects such as the glassy-winged sharpshooter
Pierce’s disease
A destructive louse that feeds off the roots of vinifera vines
Phylloxera
What is the difference between climate and weather?
Weather is the actual meteorological conditions experienced whereas climate is the historical average weather of a place. Climate is long term and weather is short term.
How much water do grapevines need on an annual basis
20 - 30 inches
Explain why soils with low fertility are generally ideal for commercial vineyards
Encourage the vine to produce less vegetation and fewer grapes
Put these four soil types in order, from smallest to largest, gravel, silt, clay, and sand
Clay, silt, sand, gravel
Describe the potential differences between a vineyard situated at a high elevation and one situated on a valley floor
A v.yard at a higher elevation will be cooler, windier, and may have less fog. The lower altitude v.yard will also have more intense sunlight and larger diurnal temperature swings.
Explain the effects that larger bodies of water have on the climate of a nearby vineyard
V.yards located close to water experience far less temperature variation than those without water influence. Bodies of water provide a source of humidity.
T/F
In general, a lower latitude translates into a warmer climate
True
T/F
The Oechsle system of measuring grape ripeness is widely used in France
False
T/F
Photosynthesis slows, but does not stop, at night
False
T/F
The annual growth cycle of a vine is considered to begin each year with bud break, which starts once temperatures reach 65 F in the spring
False
T/F
When producing dry table wines, the typical time from bud break to harvest is 140 - 160 days
True
T/F
Ideally, soil should enable the vine’s roots to access water when needed, but also ensure that excess water is drained away
True
T/F
In the N. Hemisphere, a vineyard on a slope that faces north gets the most sun
False
T/F
Regions with a continental climate generally experience hotter summers and colder winters than regions with a Mediterranean
True
T/F
Transpiration is the process by which water evaporates through opening on the underside of the leaves known at stomata
True
T/F
A Med. Climate is considered to have too short a growing season in order for grapes to ripen on a regular basis
False
T/F
In general, sugar as measured by degrees Brix will convert to alcohol by a conversion factor of 55%
True
T/F
Photosynthesis tends to slow down at temperatures below 50 F
True
T/F
A refractometer is used to measure the amount of rainfall that penetrates the topsoil to a depth of 6 inches
False
T/F
Head trained vines - sometimes referred to as gobelet style vines - do not typically require vine trellis systems
True
What best describes the process of Veraison?
The grapes begin a sudden acceleration toward maturation and begin to take on color
What is considered the ideal latitudes for commercial wine grape growing in both the N. and S. Hempisheres?
Between 30 and 50 degrees
What vineyard disease is easily spread by the glassy-winged sharpshooter
Pierce’s disease
Vine metabolic process in which sugar is broken down and converted into biological energy
Respiration
What temperature signals the beginning of a bud break in the spring?
50 F
What is most likely to occur after Veraison?
- Acidity levels fall
- Red grapes start to turn color and darken
- Sugar levels rise
Describe the ideal conditions for photosynthesis
warm days, long days, sunny skies, minimal shading, southern aspect (northern aspect in the Southern Hemisphere), well-managed vine canopy
On a grapevine, the cordons are part of the plants ______
Canopy
What type of malady is oilidum?
Fungal disease
What type of malady is Pierce’s Disease?
Bacterial disease
Portion of the vine that includes leaves, branches, and fruit
Canopy
The vines branches, while they are young and pliable
Canes
Inserting an unrooted cutting into the trunk of an existing vine
Field Grafting
Vines begin to decline at this age
20 years
Sap flowing upward from the trunk out the canes (before the emergence of new grennery)
Weeping
At the beginning of the growth cycle of the vine - tiny shoots emerge
Bud Break
Transition from flower to berry
Fruit set
Condition in which many flowers do not develop into grapes
Coulure
Abnormality resulting in many small, seedless berries in the grape bunches
Millerandage
The beginning of ripening
Veraison
Typical time period from bud break to harvest
140 to 160 days
French term for the combined natural factors of a vineyard site
Terroir
Fungal disease known as oidium
Powdery Mildew
Fungal disease known as peronospora
Downy Mildew
Root eating louse of great threat to vineyards
Phylloxera
The two main approaches to pruning
Spur pruning
Cane pruning
Vine training system that does not use supports nor trellises
Head training (bush training)
Vine training system that guides vines up a tall support
Pergola
Vine training system that guides one or two canes or cordons along a trellis
Guyot
3 examples of divided canopy systems
- Geneva Double Curtain
- Lyre
- Scott Henry
