What are (4) advantages/ (2) disadvantages of organic fertilizers?
AD - cheap/free
- high in humus = good for soil structure + water retention.
- provide nutrition for soil organisms.
- Nutrients become available for soil more gradually = longer lasting.
DIS - they need to be broken down into inorganic = requires incorporation into soil = labour/cost.
- Bulky = expensive to transport/spread.
What are (4) disadvantages of cultivation as a method of weed control?
- repeated = can damage soil’s structure/ecology via breakdown of organic matter/destruction of habitats.
- requires skilled labor + machinery = costly
- can increase vigour too much (no competition)
- can actually bury seeds, encouraging weeds to grow back.
Why is it advantageous for grape growers to remove weeds from the vineyard (3)?
- Weeds compete with vines for resources (water/nutrients)
- Weeds can increase risk of frost by blocking heat that would be absorbed by soils.
- Weeds can impede machinery/personnel (e.g. stinging nettles)
Why would artificial drainage channels need to be installed in a vineyard?
When does this need to be done?
What are advantages to this practice (2)?
- Vineyard receives plentiful rainfall but soils are not free-draining (like gravel soils in Médoc are.)
- Must be done before vineyard is planted.
1) Healthier, better balanced vines that ripen fruit consistently.
2) Aids mechanization by providing better driving surface.
What are disadvantages of drip irrigation (4)?
- high installation costs
- clean water required to prevent blockage
- drippers can become blocked anyway by algae/minerals/bacteria/salt = more maintenance.
- cannot be used in frost protection (drippers are below upper parts of vine)
What are (2) advantages of cultivation as a means of weed control?
- doesn’t use chemicals (suitable for organic / biodynamic)
- enables cover crops to be incorporated into soil at same time as removing weeds.
What is the source of mineral fertilizers?
What is their purpose?
- Extracted from the ground or chemically manufactured.
- Purpose is to provide a single nutrient or several nutrients lacking in the soil.
What are 3 types of herbicides?
1) pre-emergence: sprayed before weeds establish and persist on surface of soil
2) contact: sprayed on established weeds and kill green parts it contacts
3) systemic: sprayed on established weeds and are taken in by leaves and kill whole plant
What are disadvantages of cover crops (3)?
- reduction in vine vigour (via competition) that can be excessive in poor soils/dry environments
- difficulty of mowing under-row area = time/labour
- unsuitable for steeply sloping vineyards (slippery when wet)
3 regions that have experienced shortages in water supply in recent times:
Why?
Australia / California / S. Africa
Prolonged periods of dry weather.
Drip irrigation is the ___ ___ type of irrigation used in vineyards.
Describe how it works (3):
- Most Common
1) Pipes laid along each row (tied to lowest trellis wire)
2) Drippers fitted at appropriate intervals
3) Positioned away from vines to encourage root growth
What are the 4 key components relating to soil health?
- Soil structure: Good drainage, sufficient water-holding capacity, sufficient O, erosion resistance, root penetration ability.
- Organic Matter / Humus: decomposing organic matter which supplies nutrients, improves soil structure+water-holding capacity.
- Living Organisms: earthworms+microbes breakdown organic matter into humus/inorganic nutrients that are accessible to the vine.
- Nutrients: Total amount of available nutrients needed for the vine to grow successfully.
What are some steps a grape grower / winery can take to increase efficacy of water (7)?
- use of water-efficient irrigation systems (e.g. drip / RDI)
- use of drought-tolerant grapes (e.g. Grenache) + rootstocks
- reducing evaporation (e.g. mulch)
- reducing competition (e.g. removing weeds)
- increasing humus levels = better water retention (e.g. compost)
- re-using water for irrigation (e.g. after being used for cleaning)
- promoting depth of vine root growth (e.g. cultivation)
What are the (3) advantages / (3) disadvantages of Regulated Deficit Irrigation?
AD: - vine growth/grape development are better controlled.
- less water needs to be used.
- especially advantageous for black grapes (reduced grape size = grater concentration of anthocyanins/tannins)
DIS: - timing of application/monitoring of water levels is crucial = need for skilled labor, special equipment.
- prolonged stress can lead to yield/quality reductions.
- even if successful, often results in lower yields, meaning improvements in quality must outweigh loss of quantity.
What are (3) disadvantages of mulching?
- tends to be bulky = expensive to transport/spread.
- a lot is required to be effective.
- can increase vigor too much because of lack of competition.
What is mulching?
The spreading of matter onto the vineyard soil to suppress growth of weeds (usually biodegradable materials e.g. straw/bark chips)
Why is water quality an important consideration for vineyard irrigation (2)?
- Water high in dissolved solids (mud) = blocked sprinklers = needs filtering.
- Water high in salinity = difficulty for roots to take up water, vine dehydration = green parts will wilt/die.
What are advantages of animal grazing as a method of weed control (3)?
- no chemicals (suitable for organic/biodynamic)
- they provide vineyard with manure
- they’re a source of meat for humans
What is Regulated Deficit Irrigation?
When is it usually scheduled / why?
What type of irrigation system is used?
- a system of timing and regulating the amount of irrigation so the vine is put under mild-moderate water stress for a specific time within a growing season
- usually scheduled between fruit set and véraison to limit further shoot growth/encourage grape development.
- drip system used
What is channel irrigation?
Similar to flood, but water flows down furrows dug between vine rows (more efficient)
What is the most common type of contact herbicide used by grape growers?
Where has usage of this posed a problem?
- Glyphosate.
- High usage in S. Africa has led to glyphosate-resistant ryegrass.
What are advantages of mulching (3)?
- doesn’t use chemicals (can be used for organic/biodynamic)
- can reduce water evaporation from soil (good in dry climates)
- can be a source of humus/nutrients
What are advantages of drip irrigation (4)?
- economic use of water.
- possible to control water supply to individual rows / blocks
- can be used to apply fertilizer (“fertigation”)
- can be used on slopes
How are overhead sprinklers used for irrigation?
What are PROS (2) / CONS (2)?
Overhead sprinklers are installed above the vines, water is pumped into them and then showered over the vines.
PRO: can be used as a method of frost protection.
- more targeted approach than flood irrigation.
CONS: expensive to install/maintain due to high pressures needed.
- uses a relatively large amount of water vs drip irrigation.
-
1. The Vine41
-
2. The Vine Growth Cycle50
-
3. The Growing Environment80
-
4. Approaches to Grape Growing34
-
5. Vineyard Establishment42
-
6. Managing Nutrients + Water37
-
7. Canopy Management48
-
8. Hazards, Pests & Diseases75
-
9. Harvest17
-
10. Viticulture Scenarios23
-
11. Wine Components28
-
12. Approaches to Winemaking17
-
13. General Winemaking Options91
-
14. Maturation51
-
15. Finishing and Packaging102
-
16. Specific Options for White Winemaking38
-
17. Specific Options for Wines with Residual Sugar30
-
18. Specific Options for Red Winemaking52
-
19. Specific Options for Rosé Winemaking18
-
20.1 Producing Inexpensive, High-Volume White Wine14
-
20.2 Producing Premium, Small-Volume White Wine21
-
20.3 Producing Inexpensive, High-Volume Red Wine17
-
20.4 Producing Premium, Small-Volume Red Wine19
-
Rootstocks6
