Viticulture Flashcards
Define Stomata.
Stomata are the openings on the underside of a plants leaves.
What is respiration?
Respiration is the biological breaking down of chemicals like sugar or malic acid for the purpose of releasing energy to fuel growth. Oxygen is consumed, and carbon dioxide and energy are released.
What are three examples of divided canopies?
The Geneva Double Curtain, Lyre and the Scott Henry System are examples of divided canopies
What is vegetative propagation?
Taking a cutting or offshoot from a vine and encouraging the growth of new roots.
What is a canopy?
The arms, leaves, and grape bunches of a vine.
What does the term “third leaf” refer to?
The third year after planting or grafting a vine, where the grapes are normally considered suitable for harvesting.
How long after bud break does flowering occur?
40-80 days.
About how long after fruit set does Veraison occur?
About one and a half months.
How long after Veraison begins is a grape ready for harvest?
1.5-2 months.
What is the normal length of time from bud break to harvest?
140-160 days. Can be as short as 110, or as long as 200.
At what temperatures does photosynthesis slow?
Under 50°F and over 95°F
What effect does temperature have on respiration?
For every 18°F increase in temperature, the rate of respiration doubles.
What effect does drought have on transpiration?
If not enough water is available through the roots to meet needs, the stomata will close. Since the stomata also control the intake of carbon dioxide, photosynthetic activity will stop as well.
What is transpiration?
The process where water evaporates through stomata (openings on the bottom of the leaves), cooling the vine. The rate is highest when hot/sunny, lowest when cool/wet.
How much precipitation do vines need annually?
20-30 inches of water.
Which type of soil has very fine particles that fit together tightly?
Clay
What is cane pruning?
All but one or two canes are removed. The remaining canes are attached to a horizontal trellis and trimmed so each cane has 6-10 nodes.
What is spur training?
Vines are trained to develop one or more permanent cordons, each supporting several canes. These canes are cut back, leaving behind several spurs. Each spur contains several nodes.
What is millerandage?
An abnormality resulting in many small, seedless berries in the grape bunches, sometimes caused by bad weather during flowering.
What is Coulure?
A condition in which many flowers do not develop into grapes, often caused by windy, rainy weather during flowering until before fruit set
What is the scientific name of powdery mildew?
Oidium
What is the scientific name for downy mildew?
Peronospora.
What is a Guyot?
A system where one or two canes or codons from each vine are trained along a wire.
What is Kimmeridgian marl?
A limestone-rich soil formed by fossilized marine deposits from an ancient sea. It has excellent water retention, heat retention, and heat reflection.