Nutrient Management

Question 1

What techniques are used to control the level of nutrients in the soil?

Answer 1

• direct application of nutrients
• promotion of biological activity and soil structure
• weed management

Question 2

Why are weeds undesirable?

Answer 2

• they compete with the vine for nutrients
• they can increase risk of frost damage
• they can hamper the passage of machinery and personnel

Question 3

Describe the use of fertilizers.

Answer 3

two types: organic and mineral

• they can be added before planting to help the growth of young vines
• they can be applied to established vineyards to correct nutrient deficiencies

Question 4

What are organic fertilizers?

Answer 4

Derived from fresh or composted plant or animal materials

Question 5

What are the advantages of organic fertilizers?

Answer 5

• cheap or even free
• can be good for soil structure and water retention
• provide nutrition for soil organisms and promote living matter in the soil

Question 5

What are mineral fertilizers?

Answer 5

Fertilizer that is extracted from the ground or chemically manufactured

Question 5

What are disadvantages of organic fertilizers?

Answer 5

• require labor to incorporate them into the soil
• can be bulky and difficult to transport or spread

Question 5

What are advantages of mineral fertilizers?

Answer 5

• can be tailored to suit the nutrient requirements of the vineyard
• inorganic form can be readily available to the vines
• more concentrated, cheaper to transport and easier to distribute

Question 6

What are the disadvantages of mineral fertilizers?

Answer 6

• no benefit for soil organisms
• do not improve soil structure
• can be expensive

Question 7

What is cultivation?

Answer 7

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

Question 8

What are the advantages of cultivation?

Answer 8

• does not use any chemicals, can be used in organic and biodynamic agriculture
• enables fertilizer and mown cover crops to be incorporated into the soil at the same time as removing weeds

Question 9

What are the disadvantages of cultivation?

Answer 9

• repeated cultivation can damage the soil’s structure and ecology due to the breakdown of organic matter and destruction of habitats
• costly, as it requires both skilled labor and machinery
• disturbing the soil buries seeds, thus encouraging weeds to grow back
• can increase vine vigor too much, as there is no competition for water or nutrients

Question 10

What are the three types of herbicides?

Answer 10

1. pre-emergence herbicides
2. contact herbicides
3. systemic herbicides

Question 11

When are pre-emergence herbicides sprayed?

Answer 11

• before weeds establish
• they persist in the surface layers of the soil, but are absorbed by weeds’ roots and inhibit germination of young seedlings

Question 12

How do contact herbicides work?

Answer 12

• sprayed on established weeds
• kill the green parts of the weed that they contact

Question 13

How do systemic herbicides work?

Answer 13

• sprayed on established weeds
• taken in by the leaves, travels through the weed in the sap and kills the whole plant

Question 14

What are three advantages of herbicides?

Answer 14

1. cheap in terms of labor and machinery requirements
2. highly effective, particularly in the under-row area
3. less damaging to soil structure than cultivation

Question 15

What are four disadvantages of herbicides?

Answer 15

1. risks of poisoning to the operator, consumer, and environment, and do not encourage vineyard ecosystems
2. weeds can become resistant, and therefore larger doses or different chemicals need to be used
3. they can increase vine vigor too much, as there is no competition for water or nutrients (not necessarily a disadvantage in low vigor sites
4. not allowed in organics and biodynamics

Question 16

What are the 5 main methods of weed control?

Answer 16

1. herbicides
2. animal grazing
3. cover crops
4. cultivation
5. mulching

Question 17

What are 3 advantages of animal grazing?

Answer 17

1. does not use any chemicals, suitable for organics and biodynamics
2. animals can provide the vineyard with manure
3. animals can be a source of meat for humans

Question 18

What are 3 disadvantages of animal grazing?

Answer 18

2. vines must be trained high or otherwise animals may eat leaves and grapes off the vines
3. animal care may require labor
4. animals are often susceptible to vineyard pesticides

Question 19

What are cover crops?

Answer 19

Plants that are specifically planted, or allowed to grow, that have a beneficial effect on the vineyard.

Question 20

Name 6 reasons why cover crops might be used.

Answer 20

1. grown to suppress weeds
2. planted to improve soils structure
3. compete with the vine for nutrient and water availability in fertile sites
4. manage soil erosion
5. enhance biodiversity
6. provide a stable surface to drive vineyard machinery on

Question 21

What are examples of cover crops?

Answer 21

• legumes (beans or clover)
• cereals (ryegrass or oats)

Question 22

Why might a grower choose to leave natural vegetation as a cover crop?

Answer 22

- cheap - good for biodiversity

Question 23

What is green manure?

Answer 23

cover crops of vegetation that are ploughed into the soil

Question 24

What are 3 advantages of cover crops?

Answer 24

1. does not use any chemicals, so common in organic and biodynamic viticulture 2. the ability to influence the vigor of the vine by introducing competition 3. provision of a good surface for machinery, particularly in climates with high annual rainfall

Question 25

What are 3 disadvantages of cover crops?

Answer 25

1. a reduction in vine vigor that can be excessive in poor soils and dry environments 2. the difficulty of mowing the under-row area, particularly near the vine trunks, which has implications for time and labor 3. unsuitability for steeply-sloping vineyards, as they are slippery when wet.

Question 26

Define mulching.

Answer 26

The spreading of matter onto the vineyard soil to suppress the growth of weeds.

Question 26

What are mulches typically made of?

Answer 26

Biodegradable materials, such as straw or bark chips

Question 27

What are 3 advantages of mulching?

Answer 27

1. chemical free, used in organics and biodynamics 2. reduces evaporation from the soil, which is advantageous in dry climates 3. source of nutrients and humus, which promotes biological activity and soil structure