Seminar 2

Question 1

What is the difference between species and cultivar?

Answer 1

Species is the larger group or family name. For this purpose, it’s Vitis Vinifera.

Cultivar = grape variety or the specific type of Vitis vinfiera. For example, Chardonnay, Pinot Noir.

Question 2

How did the cultivar family develop?

Answer 2

Crossings and human intervention. The cultivar family grew over the course of centuries. Today there are 6000 - 7000 known cultivars.

Humans played a big role in the selection process

Question 3

What species is cultivated in most wine producing countries?

Answer 3

Vitis Vinifera

Question 4

How were vines reproduced in the past?

Answer 4

Through the process called layering.

Make a hole near the vine. Carefully bending the cane, bend it down into the hole. This cane will grow roots and have a life of its own. Eventually it will produce it’s own grapes. Vineyards with this type of propogration looked like a jungle.

Question 5

Why was the layering method abandoned?

Answer 5

Phylloxera. Layering the cane under the soil made it easier for phylloxera to attack the roots. Vine would die after 3-4 years.

Question 6

What is ampelography?

Answer 6

The study of vine, study of the shape of the vine.

Question 7

What is the name of the organ which anchors and supports the vine (hint it winds around the wires) ?

Answer 7

Tendril

Question 8

What is the name of the plant growth that develops from the rootstock of grated vines?

Answer 8

Sucker

Question 9

What happens to the vines in the winter?

Answer 9

Become dormant, it’s a period of rest.

Question 10

How do growers protect their vine stocks against the cold in winters?

Answer 10

A process called hilling up. Putting earth around the stock against the cold. As well as pre-pruning, leaving some canes in case of spring frost, hoping one survived.

Question 11

What are the good and bad points of winter frost?

Answer 11

Good: As long as it doesn’t go below -15/-18 degrees Celsius, the plant goes dominate. Allows it rest. Also it’s antibacterical. Kills pests, bacteria, and larva.

Bad: Winter frost can be problematic and lead to serious consequences if temperatures reach extremely low levels (below -15 degrees Celsius) in a hurry or after a mild spell. This situation can be fatal for the vine stock and thus call into question several years of harvest. The vine is then frozen in depth leading to the death of the plant.

Question 12

How do growers know that winter is over in their vineyards?

Answer 12

When you see sap at cane, also called Tears of the Vine. Once they see this they prune the vines with sharp and clean secateurs.

Question 13

What are the weather conditions for bud burst?

Answer 13

Spring above 10 degrees Celsius. Usually in March.

Question 14

What is the purpose of pre-pruning?

Answer 14

To leave some of the canes on in case of a spring frost, hoping one will survive.

Question 15

What is the principle of Guyot pruning?

Answer 15

Original idea was to increase the yield.

Single guyot pruning: 1 cane, 5-7 buds

Double guyot pruning: 2 canes, 10-14 buds.

Question 16

What do growers do with the canes they cut when pruning?

Answer 16

A few different things can happen. Shred, burn, or compost them. Now it’s suggested to collect them and turn them into fuel. Below are the problems associated with some of the methods.

1.) Cutting (shredding) many vines are infected. Problem with this is they are introductions bacteria into the soil.

2.) Burn them. Problem with this it pollutes the air. Since the canes are green, they create a lot of smoke and CO2 when burned.

Question 17

What does plowing down consist of?

Answer 17

Plowing down is removing the earth around the stock that was placed there during the “hilling up” process. At this time the winegrower also irrigates the soil and weeds it.

Question 18

What most a grower pay attention to when tying down?

Answer 18

Not to break the buds or the canes. It’s best to do in humid or rainy weather when the canes are more moldable. Classically this is “women’s work”.

Question 19

Why is de-suckering a necessary task? How do growers do it?

Answer 19

Suckers keep growing, 1.5 m in a year. Once they lignify (become harden) you need sharper tools, easier to do when they are young.

Question 20

What is the best weeding method?

Answer 20

By hand is the best method.

Question 21

How do growers fight spring frost?

Answer 21

1.) Light barrel fires called bougies.

2.) Large fans

3.) Helicopters (not as common)

4.) Sprinklers, which help to keep the temperature above freezing.

Read more here: https://www.decanter.com/learn/winemakers-prevent-frost-ask-decanter-367606/

Question 22

What is the pollinating agent of vines?

Answer 22

Vines are self-pollinating, a hermaphroditic plant. Wind/air carries pollen to help with this process.

Question 23

Why is rain bad during flowering?

Answer 23

When a rain occurs during flowering, it can cause something called “stuck caps”.

The flower parts of a vine are contained inside a “cap”. These normally fall off at the start of flowering to reveal the reproductive parts of the flower.

Stuck caps can create issues in two ways…

1.) They can stop the fertilisation of that flower. If the flower isn’t fertilised then no berry is formed (so this can affect yield)

2.) A stuck cap is a source of infection for bunch rots (a group of diseases). The most common bunch rot is botrytis.

Question 24

What is the name of the stage during which grapes take their shape?

Answer 24

Setting

Question 25

Why is tying up often a race against time?

Answer 25

Shoots grow very fast, in June or end of May. They can grow 5 cm in 24h. When the nights are warm, they keep growing. Need to tie up before they lignify (harden).

Question 26

What is veraison?

Answer 26

Color change that usually occurs 6 weeks after flowering.

Typically takes 4-5 days of dry weather, if they weather is cold and rainy it can take longer like 3 weeks.

Question 27

What are the good and bad points for rainfall in the vineyard cycle?

Answer 27

Good: During Winter
Bad/avoid: flowering, a little before harvest, and during harvest

Question 28

Why is the bottom of a valley a poor location for a vineyard?

Answer 28

Too fertile, too wet, too cold, and poor sun angles

Question 29

What can growers do in case of hail threats?

Answer 29

Nets (but block the sun by 15%) and not allowed in very country.

Also, can shoot silver iodide into the sky. This just causes it to storm somewhere else.

Question 30

Why are new vineyards often planted higher on the hills?

Answer 30

Drainage, better aspect, and climate change.
With warming temperatures, the higher you plant the cooler it is.

Question 31

What do growers do prior to re-planting a vineyard?

Answer 31

Disinfect the soil!! Fear of nematodes and fan leaf disease.

Question 32

In what months are vineyards traditionally replanted?

Answer 32

Vines: replanted in April, however now that winter doesn’t really exist anymore (or it’s more mild) winegrowers also tend to re-plant vines in November as well.

Traditionally November 25th on the day the French replanted trees. The French celebrated St. Catherine. There is a saying, “all trees take root” this day.

Question 33

How often do growers trim their vines?

Answer 33

Three times a year, typically: June, July, August

Question 34

What is the purpose of the green harvest?

Answer 34

It is done before veraison (typically July) to eliminate bunches for yield control. Traditionally they will eliminate one out of three bunches. Also allows the winegrowers to ensure space between the bunches to avoid diseases.

Question 35

What are the pros and cons of de-leafing?

Answer 35

Pros: Opens the canopy, allowing air flow and sun to help maturation of grapes. Plus it makes the grape pickers work easier. If possible do this on the north side.

Cons: Risk sunburning the grapes.

Question 36

What happens to the vine shoots in the course of the summer?

Answer 36

Lignification, the sugar in the form of starch moves from the rootstock to the shoots and tendrils. Making them harder. This makes the job of the pruners harder.

Question 37

What are the pros and cons of a mechanical harvest?

Answer 37

Pros: Cheaper (by 40%), can do at night if it’s too hot during the day.

Cons: Picks up everything (animals, tools, you name it), removes the stems, less selection of grapes