6. Managing Nutrients and Water

Question 1

define soil health

Answer 1

Soil health is the continued capacity of the soil to act as a living ecosystem, that sustains plants, animals, and humans.

Question 2

Soil health is related to what 4 things?

Answer 2

• soil structure
• amount of organic material and humus
• number of living organisms in the soil (biomass)
• total amount of available nutrients for the vine

Question 3

Advantages and disadvantages of organic fertilizers?

Answer 3

Adv:
-Cheap, even free
-Promote living matter in the soil
Dis:
-Require incorporation into soil, which requires labor.
-Slow to break down and become available to the vine.
-Can be bulky therefore expensive to transport and spread

Question 4

Advantages and disadvantages of inorganic fertilizers?

Answer 4

Adv:
-can be tailored to specific needs
-nutrients readily available to vines
-cheaper to transport and distribute
Dis:
-hold no benefit for soil oganisms
-do not improve soil structure
-more expensive

Question 5

What is cultivation?

Answer 5

method of weed control that involves ploughing the soil to cut or disturb weed root systems

Question 6

Advantages and disadvantages of cultivation?

Answer 6

Adv:
-does not use chemicals so can be used in organic and biodynamic viticulture
-enables fertilizer and mown cover crops to be incorporated into soil at the same time as removing weeds
Dis:
-Repeated cultivation can damage soil structure and ecology
-costly - requires skilled labor and equipment
-buries seeds, encouraging weeds to grow back
-can increase vine vigor

Question 7

What are the three types of herbicides?

Answer 7

1. Pre-emergence herbicides are sprayed before weeds establish
2. Contact herbicides sprayed on established weeds
3. systemic herbicides that are taken in by leaves.

Question 8

Advantages and disadvantages of herbicides?

Answer 8

Adv:
-cheap in terms of labor and machinery
-highly effective
-less damaging to soil structure than cultivation
Dis:
-risk of poisoning operator, consumer, environment
-weeds can become resistant
-can increase vine vigor - no competition
-not allowed in organic/biodynamic viti.

Question 9

advantages and disadvantages of animal grazing?

Answer 9

Adv:
-does not use chemicals so allowed in organic/biodynamic viticulture.
-animals provide manure
-animals are edible
Dis:
-vines must be trained high enough so animals don’t eat them
-animals need caring
-animals susceptible to vineyard pesticides.

Question 10

Advantages and disadvantages of cover crops?

Answer 10

Adv:
-does not use chemicals and increases biologic activity and vineyard biodiversity, common in organic/bio
-ability to influence vigor of the vine through competition
-provide good surface for machinery
Dis:
-reduction in vine vigor can be excessive
-difficulty moving under-row area
-unsuitable for steep slopes

Question 11

Advantages and disadvantages of mulching?

Answer 11

Adv:
-does not use chemicals so friendly for organic/bio
-can reduce water evaporation from soil
-ultimately good source of nutrients and humus, promoting good soil structure.
Dis:
-bulky, so expensive to transport and spread
-only effective if applied in a thick layer, so a lot can be required
-can increase vine vigor too much

Question 12

Types of irrigation?

Answer 12

• drip
• flood
• channel

Question 13

Advantages and disadvantages of drip irrigation?

Answer 13

Adv:
-permit economic use of water
-possible to control water supply to individual rows, blocks, vines
-can supply fertilizer
-can be used on slopes
Dis:
-high cost of installation
-clean water required, or blockage can happen
-cannot be used in frost protection

Question 14

What is Regulated Deficit Irrigation (RDI)?

Answer 14

A system of timing and regulation the amount of irrigation so that the vine is put under moderate water stress for a specified time within the growing season. Usually between fruit set and verasion to limit further shoot growth and encourage grape development

Question 15

What are beneficial properties to good soil structure?

Answer 15

• good drainage
• sufficient water-holding capacity
• sufficient oxygen
• ability to resist erosion
• allow vine roots to penetrate to sufficient depth

Question 16

What can poor soils health lead to?

Answer 16

• Can lead to problems with the availability and uptake of nutrients and water, hence poor vine growth and poor ripening

Question 17

What is organic matter and humus in soil referring to?

Answer 17

• decomposing organic matter that supplies nutrients

- humus improves soil structure and water-holding capacity

Question 18

What is the role of earthworms and microbes in relation to vineyards?

Answer 18

They break down organic matter into humus and inorganic nutrients that are accessible to the vine

Question 19

When are fertilizers generally applied?

Answer 19

Before planting to help young vines grow and applied to established vineyards to correct any detected nutrient deficiencies

Question 20

What happens if too much fertilizer is applied?

Answer 20

Can lead to excess vine vigor and unbalanced vines

Question 21

Advantages/disadvantages of flood/channel irrigation?

Answer 21

Cheap to install and maintain, but it’s inefficient as a lot of water is not taken up by the vine. Can only be used on flat or gently sloping land.

Channel irrigation is similar, only using channels for water. the same adv/dis apply.

Question 22

How is water regulated in areas with high rainfall in the growing season?

Answer 22

Drainage systems installed before establishing vineyard.

• leaving natural vegetation to grow or planting specific crops to provide competition for water
• improving soil structure and removing any plough pans to better regulate water drainage.