Understanding Vineyard Soils Flashcards
R.E. White (2009)
How many species of plant parasitic nematodes have been recorded on grapevines?
60
Name the four main species of Plant Parasitic Nematodes
Root-Knot
Root-Lesion
Dagger
Citrus
Which nematode is a vector for fan leaf virus? You need to know the Linnaean Taxonomy.
California Dagger Nematode or Xiphenema Index
What pre-planting fumigants can be used in vineyard soils for nematodes?
Furfural & Dichloropropene
Which soil type encourages nematodes the most?
Sand.
What are the four foundation species of rootstock?
Vitis Berlandieri
Vitis Rupestris
Vitis Riparis
Vitis Champinii
What are the three chemical tests for soil biological health?
- Soil Microbial Biomass
- Soil Organic Carbon
- Potentially Mineralizable Nitrogen
Do manures effectively combat soil acidification?
Yes.
What is Bio-Char?
Charcoal used as a soil amendment made from pyrolised biomass.
What would be the best cover crop in high vigour sites with high water availability?
Perennials such as Chickory for structural improvement and to maintain soil structure.
What cover crops are best for high winter rainfall and dry summer sites?
Winter annuals such as oats, barley or ryegrass that can be sown in summer and don’t compete for water during the growing season.
What are the four advantages of cover crops for soil texture?
Cover crops:
- Improve structure
- Help with the infiltration of water
- Improve soil strength
- Help with drainage
What are three chemical functions of soil organic matter?
Soil organic matter functions to:
- Cation exchange
- Soil pH
- Binding soil organic matter to soil minerals
What are three biological properties of soil organic matter?
Biologically, soil organic matter:
- Is an energy source
- Is a nutrient reservoir
- Assists with resistance of infection
What are three physical properties of soil organic matter?
Physically, soil organic matter:
- Helps with structure and stability
- Assists with water retention
- Acts as a thermal regulator
What is a bio-pesticide?
A naturally occurring bacterium or parasite that acts as an insecticide in a vineyard.
Name a specific bio-pesticide and describe it’s mechanism of action.
Bacillus Thuringiensis is a is a Gram-positive, soil-dwelling bacterium that occurs naturally in the gut of caterpillars of various types of moths and butterflies. During sporulation, many Bt strains produce crystal proteins called δ-endotoxins, that have insecticidal action on nematodes.
What is a brand name of a bio-inoculant?
Trich-a-Soil (Australia)
What are the three major constituents of bio-inoculants and what are their functions?
Gibberellins (GA’s): Regulate developmental processes including stem elongation and flowering.
Auxins: Phytohormones that dominate external stimulus response to light.
Cytokinins (CK): Hormones that promote cell division in roots and shoots.
What are the two advantages of micro-jets for irrigation?
- They deliver water a higher rate
- They better distribute water on sand, allowing cover crops in warm climates with sandy soils where drip irrigation would drain much faster with much less cover.
What are the 4 determining factors of irrigation method?
- Topography and soil type
- Availability and price of water
- Capital cost of installation
- Skill of vineyard staff
What are the 4 best practices of soil salinity management?
- Keep the leaching requirement as low as possible by using low-saline irrigation water.
- Use salt-tolerant rootstocks such as 1103Paulsen or Ramsey.
- Match the application of water to the vine demand using visual and ET data.
- Monitor drainage
What are two non-mechanical ways to improve soil drainage?
- Gypsum
2. Fibrous root grasses or deep tap root cover cropping.
What are three mechanical methods to improve soil drainage?
- Deep ripping
- Perforated PVC ‘aggi’ pipes
- Avoid compaction through eschewing machinery use.
Benefits of organic mulches mid-row?
They have low thermal conductivity and slow the transfer of heat in/out of the soil which means cooler daytime soils and warmer nighttime soils at high diurnal sites.
What is Albedo? Why does it matter?
Albedo: The measure of the diffuse reflection of solar radiation.
Mulches have higher albedo than bare soil, reflecting more light resulting in cooler soils.
What are four benefits of mulches, chips or cereal straw mid-row or undervine?
- Shading. Reducing soil water evaporatioon
- Supressing weeds. Use less herbicide.
- Rain drop splash prevention that helps to maintain soil structure.
- Encourages biological (worm) activity.
Why keep the mid-row mown during the growing season?
- Reduces evapotranspiration
- Improves yield by eliminating competition
- Reduces frost risk by allowing free movement of air.
What are three advantages of cover crops?
- Dries soil and controls vigour
- Improves soil strength and trafficability
- Protects from erosion and winter rains.
What is Abscisic Acid?
Abscisic Acid is a plant hormone with functions including the regulation of dormancy and stomatal closure. It is especially active in response to environmental stress such as hydric/heat stress.
What is the physiological plant response to partial root-zone drying?
Abscisic Acid from the roots tricks the plant into responding to false hydric stress, closing stomata and reducing water loss through the leaves.
Define Field Capacity
“Measure of the upper threshold of water available in the vineyard when gravitational seepage slows or stops.”
Define Aeration
– Pore space filled with water in the soil drains, leaving vacuous oxygen and nitrogen gas.
– Plant roots consume the gas and release carbon dioxide into the atmosphere.
– This exchange is aeration.
What are the three traditional methods of soil mapping?
- Aerial photography
- Auger samples
- Soil pits
What are the two types of igneous rock, their characteristics, and an example from the world of wine where they occur.
Acidic Igenous Rock (Granite Belt): Coarse and well-draining.
Basic Igneous Rock (Willamette Valley): Deep loams, finer texture and less free-draining.
What is sandstone?
Soil made of compressed sand, quartz, feldspar and rock.
What is dolomite?
A type of limestone that is especially magnesium rich.
Textbook definition of limestone.
“A sedimentary rock formed by calcium carbonate minerals or calcified skeletons of marine life deposited in ancient sea beds.”
Formula for Calcium Carbonate
CaCO3
What are the three types of soil profile?
Uniform, Gradiational and Duplex
What are the four basic ecosystem functions of soil?
- Nutrient Cycling
- Supporting biodiverity
- Storing and filtering water
- Maintaining resilience
What are the three key need-to-know points regarding phosphorus in vineyard soils?
- Inputs from the atmosphere are negligible
- Soils levels are rarely sufficient
- AMF helps tremendously
What are the three auxiliary should-know points regarding phosphorus in vineyard soils?
- Phosphorus fixation is complicated by iron and aluminium in the soil.
- It is more important at vineyard establishment than in a mature vineyard.
- Maintenance application is based on yield from the site, at about 600g removed from the soil for each tonne of fruit harvested.
What are the ideal YAN concentrations for fermentation?
250 - 350 mgN/L
What effect does low YAN have on ferment?
Sluggish and could stick, production of H2S from stress.
What effect does high YAN have on ferment?
Rapid, poor quality, high temperature.
What is the effect of nitrogen application after fruit set?
Ideal. Has a major effect on the berry nitrogen concentrations and trunk storage.
What is the nitrogen demand of the vine from version to harvest?
Bunches are main accumulators during this time, and mainly from nitrogen remobilised from within the vine.
When are the optimal times and methods to apply nitrogen fertilisers?
- Superficially after budburst
2. After flowering and before version by fertigation or soil drench.
What are the three naturally occurring sources of Nitrogen to vines?
- Legumes and cover crops - broad beans
- Atmospheric
- Ammonia (feces, urine and fertilisers)
What is the primary purpose of soil testing?
To determine the soils ability to supply an essential nutrient or assess toxicity - most notably salt.
What are five primary need-to-know points regarding Vinifera AMF?
- It is a self-regulating symbiotic relationship
- Because vinifera is perennial, the less effective strains dominate over time.
- Mid-row crops prone to AMF can help encourage diversity of strains
- Is is important for new vines especially in poor soil
- Mycorrhizal roots live longer
What is the function of a mycorrhiza?
The fungus enhances the uptake of otherwise immobile nutrients and in turn obtains organic material for growth.
What is a mycorrhiza?
A symbiotic association between a fungus and a plant root.
What study and when authoritatively considered distinctive old-vine wine characteristics?
Swinchatt and Howell (2004) used earth process units and hypothesised that the differential uptake of nutrients at bedrock weathering such as (Ca, Mg, Fe and Mn) might explain distinctive old-vine characteristics in wine.
Soil organic matte is confined to which area of a soil profile?
The A-Horizon (10-20cm)
The grapevine has evolved to explore ___________ soil volumes at ___________ root density.
The grapevine has evolved to explore large soil volumes at low root density.
What are two examples of elemental toxicity in world vineyards?
- High nickel concentrations in Calistoga in vines grown on serpentine rock.
- Copper concentrations with prolonged use of the Bordeaux mixture in Bordeaux.
What are the six micronutrients?
Iron (Fe) Managanese (Mn) Zinc (Zn) Copper (Cu) Boron (B) Molybdenum (Mb)
What are the ten macronutrients?
Carbon Hydrogen Oxygen Nitrogen Phosphorus Sulphur Calcium Magnesium Potassium Chlorine
Which three soil additions ought be introduced during ripping / pre-planting and what are their effects?
Rock Phosphate: Phosphorus support for essential functions.
Gypsum: for soil infrastructure and drainage
Lime: to adjust pH if necessary
What is the benefit of legume cover crops in pre-plantinga vineyard?
When plowed in, can stimulate beneficial soil organisms helping vines resist pests and disease in the planting stage. General overall soil health and biomass.
Chemicals used in soil fumigation
Furfural & Dichloropropene
What is the main issue with using reclaimed water for irrigation?
Often has a high nutrient load (toxicity) and salt concentrations.
What analyses are recommended for soil irrigation water?
pH, Ca/Mg (hardness) and Fe (clogs hoses)
How are the salt concentrations in irrigation water measured? What is the threshold?
Measured in decisiemens.
Threshold is
What is the most critical factor of water quality?
The concentration of dissolved salts.
How do you calculate peak demand for a drip irrigation system?
droppers/vine * L/hr * vph = L/ha/hr
What five factors determine the total water requirement for a site?
- Soil structure
- If overhead frost sprinklers are employed
- If there is an operational on-site winery
- Climate with specific reference to rainfall
- Likely peak demand
What five factors determine a sites likely peak water demand?
- Surface area
- Cultivar
- Density
- Yield Objectives
- Irrigation Method
Define Homoclime
Planting varieties in similar climates around the world based on similar continentality/HDD indices.
Define and state the equation for HDD (Amerine and Winkler)
- Based on the summation of ‘heat units’ for the 7 months of the growing season such that:
HDD = #days * (mean daily temp - 10)
Determining a new vineyard sites suitability starts with gathering as much data on which four factors?
- Climate
- Soil types and their distribution
- Availability of water
- Potential pest/disease risk
Beyond Phylloxera resistance and Nematodes, rootstocks offer other advantages, such as:
Salt/Drought Tolerance Tolerance of free lime Vigour Control/Vine Balance Water Use Efficiency Discrimination of nutrient uptake
There are _____ known genotypes of phylloxera with different degrees of lethality.
83
Define a “Cross”
offspring obtained through cross-pollination of two varieties of the same species (Ex: Ruby Cabernet, which s a cross between Cabernet Sauvignon and Carignon)
Define a “Hybrid”
offspring obtained through cross-pollination of two different species (Ex: Vidal is a hybrid of a non-vinifera and a vinifera species).
Short history of American Hybrids
Originally bred for harsh conditions and bred between vinifera, labrusca and aestevalis to produce cultivars such as norton, concord and delaware.
What are two successfully exported french hybrid varieties?
Chambourcin and Vidal