Viticulture

Question 1

What is weeping/bleeding?

Answer 1

Vine leaks watery sap from pruned canes.

Question 2

In the Northern Hemisphere approx what month does weeping/bleeding start?

Answer 2

Typically, February

Question 3

What is budbreak?

Answer 3

First small shoots and leaves will break through buds left intact by winter pruning.

Question 4

In the Northern Hemisphere, when does budbreak usually occur?

Answer 4

Once average air temperature surpasses 50 Fahrenheit.

March-April

Question 5

What is the vine vulnerable to during budbreak?

Answer 5

Frost

Question 6

What are the small green clusters that form on shoots?

Answer 6

Embryo bunches

Question 7

When does flowering occur in relation to budbreak?

Answer 7

6-13 weeks–depending on climate

Question 8

How does the grape vine start the process of fertilization?

Answer 8

It self-pollinates!

After embryo bunches bloom into flowers for ten days it begins the process of fertilizatio.

Question 9

What is the average fruit set?

Answer 9

30%

Question 10

What is coulure?

Answer 10

Embryo berries falling from the cluster during fruit set.

Question 11

What is millerandage?

Answer 11

Some grape flowers fail to fertilize and mature at different rates.

Question 12

What is verasion?

Answer 12

Ripening.

Sugars are moved from leaf system to the fruit.

Grapes soften and change color.

Question 13

What is vendange?

Answer 13

Harvest.

Question 14

What is the preferred annual temperature for the vine?

Answer 14

50-68 Fahrenheit

Ideal–57

Question 15

What average summer temperature do red grapes prefer?

Answer 15

70 Fahrenheit

Question 16

What average summer temperature do white grapes prefer?

Answer 16

66 Fahrenheit

Question 17

What are the ideal bands of latitude for viticulture?

Answer 17

30-50 degrees

Question 18

What is photosynthesis?

Answer 18

Plants using carbon dioxide into organic compounds

Question 19

What is the minimum amount of sunshine needed to support viticulture?

Answer 19

1300 hours

Question 20

What does cloudcover affect?

Answer 20

Amount of heat the sun gives to the vine.

Does not affect photosynthesis

Question 21

How much rain does the vine require to produce adequate crop?

Answer 21

10-30 inches.

Vine is drought-resistant plant

Question 22

What is water stress?

Answer 22

Vine receives to little rain.

Promotes smaller berry size and yields, but can lead to interrupted ripening and complete shutdown of the vine.

Question 23

What does too much rain do to a vine?

Answer 23

Will not adversely affect vine itself

Leads to diluted fruit quality.

Encourages development of fungal diseases.

Question 24

Define macroclimate

Answer 24

Entire wine region

Napa Valley

Question 25

Define mesoclimate

Answer 25

Particular vineyard

Question 26

Define microclimate

Answer 26

Rows or even specific vines

Question 27

Define continental climate

Answer 27

Strong annual variation in temperature due to lack of proximity to significant bodies of water.

Hotter summers than maritime often with extreme cold winter temperatures

Question 28

Define maritime climate

Answer 28

Influenced by a large body of water such as a sea or ocean.

Marked by mild temperatures that can fluctuate from year to year, causing vintage variation.

Question 29

Define Mediterranean climate

Answer 29

Hot and dry summers, aside from immediate coastal areas.

Along coasts, summers are mild due to proxmity to cold water currents, but storms are consequence.

Question 30

Define high desert

Answer 30

Summers are generally hot and dry.

Daytime temperatures are high, but dramatic drops are often experienced overnight.

Question 31

What is a diurnal shift?

Answer 31

The difference between average daytime high adn nighttime low temperatures.

This can affect the ripening of grapes and the balancing of acidity and sugar.

Question 32

What threat does frost pose?

Answer 32

Hazard in spring and fall.
Winter freezing can cause damage if severe and can kill vines.

In spring, frost can damge or freeze and kill delicate buds or flowers, preventing the vine from setting clusters.

Question 33

What threat does hail pose?

Answer 33

Can shatter grapes on the vine.

Question 34

What threat do strong winds pose?

Answer 34

Can blow vines over or blow buds and flowers off the vine, preventing grapes from growing.

Question 35

Cordon trained

Answer 35

The vine has at least one permanent cane that extends from the trunk called an arm/cordon.

Generally require a trellising system

Question 36

Head trained

Answer 36

No permanent cordon, and trunk ends in knob or head.

Seen as alternative to trellising–can still be done.

Question 37

Guyot system

Answer 37

Developed in 1860 by Jules Guyot.

Requires vertical trellis on which canes are suspended, and has one spur and one main two year old cane.