Chapter 4 Viticulture

Question 1

Put the following stages of the annual growth cycle of the vine in chronological order, starting with winter dormancy and following through the year.

Berry set, Photosynthesis begins, Harvest, Bud break, Physiological maturity, Version, Shoot and leaf growth, Flowering, Weeping, Winter dormancy

Answer 1

Winter Dormancy
Weeping
Bud Break
Shoot and leaf growth
Photosynthesis begins
Flowering
Berry set
Veraison
Physiological maturity
Harvest

Question 2

Name the metabolic process described by the following statement.

The process by which materials are moved from one part of the plant to another.

Answer 2

Translocation

Question 3

Name the metabolic process described by the following statement.

The process by which sunlight is converted into sugar.

Answer 3

Photosynthesis

Question 4

Name the metabolic process described by the following statement.

The process by which water evaporates through openings on the underside of the leaves.

Answer 4

Transpiration

Question 5

Name the metabolic process described by the following statement.

The process by which sugar is broken down and converted into biological energy.

Answer 5

Respiration

Question 6

Match the following vine malady with its appropriate definition.

Oidium, Peronospora, Botrytis cinerea, Millerandage, Coulure, Pierce’s Disease, Phylloxera, Nematode

A problem that causes poor fruit set, also known as shatter.

Answer 6

Coulure

Question 7

Match the following vine malady with its appropriate definition.

Oidium, Peronospora, Botrytis cinerea, Millerandage, Coulure, Pierce’s Disease, Phylloxera, Nematode

A soil-based roundworm that has become more prevalent with the increased use of shallow-rooted rootstock.

Answer 7

Nematode

Question 8

Match the following vine malady with its appropriate definition.

Oidium, Peronospora, Botrytis cinerea, Millerandage, Coulure, Pierce’s Disease, Phylloxera, Nematode

A mold that is sometimes beneficial, also known as noble rot.

Answer 8

Botrytis cinerea

Question 9

Match the following vine malady with its appropriate definition.

Oidium, Peronospora, Botrytis cinerea, Millerandage, Coulure, Pierce’s Disease, Phylloxera, Nematode

A fungal disease also known as powdery mildew.

Answer 9

Oidium

Question 10

Match the following vine malady with its appropriate definition.

Oidium, Peronospora, Botrytis cinerea, Millerandage, Coulure, Pierce’s Disease, Phylloxera, Nematode

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.

Answer 10

Millerandage

Question 11

Match the following vine malady with its appropriate definition.

Oidium, Peronospora, Botrytis cinerea, Millerandage, Coulure, Pierce’s Disease, Phylloxera, Nematode

A fungal disease also known as downy mildew.

Answer 11

Peronospora

Question 12

Match the following vine malady with its appropriate definition.

Oidium, Peronospora, Botrytis cinerea, Millerandage, Coulure, Pierce’s Disease, Phylloxera, Nematode

A bacterial disease spread by insects such as the glassy-winged sharpshooter.

Answer 12

Pierce’s Disease

Question 13

A destructive louse that feeds off the roots of vinifera vines.

Answer 13

Phylloxera

Question 14

What is the difference between climate and weather?

Answer 14

Climate refers to the historical, average weather of a certain place, or what is expected to happen in the long run. Weather is the actual meteorological conditions forecast in the short term, as well as what actually occurs.

Question 15

How much water do grapevines need on an annual basis

Answer 15

Approximately 20-30 inches/51-76 cm

Question 16

Explain why soils with low fertility are generally ideal for commercial vineyards.

Answer 16

Less fertile soils encourage the vine to produce less vegetation and fewer grapes, leading to well—ripened grape bunches rich in sugar and phenolics.

Question 17

Put these four soil types in order, from smallest in particle size to largest: gravel, salt, clay, and sand.

Answer 17

Clay (smallest), silt, sand, gravel (largest)

Question 18

Describe the potential climatic differences between a vineyard situated at a high elevation and one situated on a valley floor.

Answer 18

A vineyard at higher elevations will be cooler, windier, and have less fog. The higher altitude vineyard will also have more intense sunlight and larger diurnal temperature swings.

Question 19

Explain the effect that large bodies of water have on the climate of a nearby vineyard

Answer 19

Water tends to change temperature more slowly than soil, so vineyards situated close to large bodies of water experience less temperature fluctuation. Their diurnal temperature range is less, summers are not as hot, and winters are milder. The humidity can also provide for morning or evening fogs, as well as greater cloud cover, rain, and dampness.

Question 20

T/F In general, a lower latitude translates into a warmer climate.

Answer 20

True

Question 21

T/F The Oechsle system of measuring grape ripeness is widely used in France.

Answer 21

False, it is widely used in the German, Swiss, and Luxembourgish wine-making industries.

Question 22

T/F Photosynthesis slow, but does not stop, at night.

Answer 22

False, red and blue wavelengths of light can facilitate extended photosynthesis through the night.

Question 23

T/F The annual growth cycle of the vine is considered to begin each year with bud break, which starts once temperatures reach 65ºF (18ºC) in the spring.

Answer 23

False, bud break does begin the annual growth cycle of the vine but it does so when temperatures reach 50ºF (10ºC).

Question 24

When producing dry table wines, the typical time from bud break to harvest is 140 to 160 days.

Answer 24

True

Question 25

Ideally, soil should enable the vine’s roots to access water when needed, but also ensure that excess water is drained away.

Answer 25

True

Question 26

In the Northern Hemisphere, a vineyard on a slope that faces north gets the most sun.

Answer 26

False, a vineyard in the Northern Hemisphere gets the most sun on a slope that faces south.

Question 27

Regions with a continental climate generally experience hotter summers and colder winters than regions with a Mediterranean climate.

Answer 27

True

Question 28

The Guyot system of vine training does not require the use of a trellis or wires.

Answer 28

False, this system uses trellis and wires.

Question 29

A Mediterranean climate is considered to have too short a growing season in order for grapes to ripen on a regular basis.

Answer 29

False, the Mediterranean climate is perfect for many different types of grapes.

Question 30

In general, sugar as measured by degrees Brix will convert to alcohol by a conversion factor of 55%.

Answer 30

True

Question 31

Photosynthesis tends to slow down at temperatures below 50ºF (10ºC).

Answer 31

True

Question 32

A refractometer is used to measure the amount of rainfall that penetrates topsoil to a depth of 6 inches (15 centimeters).

Answer 32

False, it is used to measure grape sugar concentration in degrees of Brix.

Question 33

In a pergola system, overhead vines are trained up a tall support and allowed to spread out horizontally.

Answer 33

True

Question 34

In the United States, a biodynamic viticulture is regulated by the US Department of Agriculture.

Answer 34

False, it is regulated by Demeter International

Question 35

Which of the following statements is true concerning photosynthesis?
A. Photosynthesis occurs most efficiently when the daytime temperature is over 90ºF (32ºC).
B. Photosynthesis occurs most efficiently when the daytime temperature is under 50ºF (10ºC).
C. Photosynthesis slows but does not completely shut down at night.
D. Photosynthesis can only occur when the sun is shining.

Answer 35

D. Photosynthesis can only occur when the sun is shining.