Vineyard Management Flashcards

(149 cards)

1
Q

What does site suitability depend on?

A

Water, climate, type and quality of soil, access to site, labor availability

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2
Q

Name an example of nutrient deficient soil

A

Sandy soil in high rainfall area - deficient in K calcium and SO2
Frequently cultivated shallow soils in low rainfall - low N

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3
Q

How many grape varieties are there?

A

8000 Winkler, wild and table

1400 Jancis commercial

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4
Q

What predetermines the style and quality of a wine most?

A

Genetic characteristics of the grape

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5
Q

Climatically, where do grapes produce their best iterations?

A

At the coolest margin of viable ripening

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6
Q

What is the calculation for planting density?

A

Per hectare, number of rows x number of vines in each row

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7
Q

Is there a direct correlation between high density planting and quality?

A

No. Though it increases the total leaf surface in a vineyard

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8
Q

What determines vine balance?

A

Vigor
Planting density
Fertility of soil
Training system

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9
Q

How does soil fertility correlate with density?

A
Poorer soil = higher root density
Poorer soil = lower vigor
Poorer soil = higher density
UNLESS low water
Fertile soil = high vigor =low density
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10
Q

How should alleys between rows be considered?

A

Alleys should never be narrower than the heights of the row canopy (so as not to cast shade on other fruiting areas)
BUT more costly

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11
Q

How to calculate distance between vines on a row

A

15 shoots per meter
Wider alleys = greater distance between plants bc wider alleys =more vigor since more soil space available
(More soil space means more trellis space)

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12
Q

What is row orientation influenced by?

A

Shape of field
Direction of slope
Wind

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13
Q

Orientation for cool climate vineyards?

A

North south =maximize sunlight in autumn

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14
Q

When did vines begin to be oriented and trellised in Europe?

A

After phylloxera

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15
Q

Why have elaborate trellising systems?

A

Control vine vigor and disease

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16
Q

What to consider when deciding on trellising system?

A
Legislation
Geography
Canopy surface/ha
Cost and time of establishment and maintenance
Mechanisation potential
Popularity and attractiveness
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17
Q

What kind of trellis system might a vintner use at the bottom of a hill?

A

Higher one to escape frost

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18
Q

What is a bush vine? Why use it and where? Disadvantages?

A
Trained short with no trellis
Common in warmer Mediterranean
Low cost and low production
Spur pruned
Basket = cane pruned

Good:
Bunch shade
Maintenance costs low

Bad:
Yields (low planting density)
Less air circulation (disease)
All manual

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19
Q

What are staked vines? Positives/negatives/where? How high are they trained? How are they trained?

A

Vines tied to a single post
Low density planting

Good:
Can be trained higher = simpler vineyard operations
Greater air circulation

Bad:
Lower yield
Not good for high vigor sites

How:
Form a crown 20-30cm above ground and 2-4 canes fixed to stake
OR spur pruned without crown

Cote Rotie, southern France, Spain, Portugal, others (new world)

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20
Q

Why is single wire better than bush?

A

Forms a continuous row

Inexpensive to install and train

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21
Q

How are single wire systems trained?

A

Cordon and spur or head and cane

Cordon:
Trunk divided 15cm below wire and permanent horizontal cordon.

Head/cane:
Crown established below wire and up to 4 canes of 10 to 15 nodes along the wire, with two to four 2 node replacement spurs

Problem:
Shoots hang down so fruit isn’t protected

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22
Q

Two-wire vertical - style and advantages

A

Single fruiting wire and single foliage water .3-.5 above

Suited to mechanical pruning and harvesting

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23
Q

What is the name for two-wire vertical in California?

A

California sprawl

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24
Q

Where is VSP used? Why? Advantages/disadvantages?

A

France, Germany, cooler Australia, New Zealand

Used in areas with high fungal disease risk - keeps foliage off the ground
Also simplified mechanical operations (foliage in one area and fruit in another
Suitable for mechanization

Has movable foliage wires

Disadvantage:
High Shoot density = prone to shade
Bad for high vigor varieties and sites
(Divided canopy helps)

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25
How is VSP trained and pruned?
Cane pruned or spur pruned on unilateral or bilateral cordons
26
What are the two main vertical divided systems?
Scott-Henry and Smart-Dyson
27
How does the Scott Henry system work?
``` Developed in Oregon, trialled in NZ and Australia (New World, machine harvest) Two fruiting wires (1 m and 1.15 m) 2m tall Top foliage = between two movable wires Bottom foliage = positioned downwards Cane pruning Machine harvesting ```
28
How does the Smart-Dyson system work?
Same as the Scott Henry system but cordon trained Spurs point upwards and downwards = two canopies Machine pruning and harvesting
29
Why are Scott Henry and Smart-Dyson superior to VSP?
Increased canopy surface = more photosynthesis and yield Shoot density is halved = increased fruit exposure De-vigorating effect because shoots are trained downwards
30
What is Guyot? Who invented it?
Replacement cane pruning system. Either single or double | Jules Guyot, 1860s
31
Name some examples of multi-wired horizontal trellis systems
Geneva Double curtain, U or lyre, overhead pergola
32
What is Geneva Double Curtain?
Horizontally divided with shoots trained downwards At least 1m apart and 1m in length Cordon/spur pruned ``` Good: Improve yield of quality fruit composition in vigorous soils Reduces shading Can be pruned and harvested by machine Devigorates ``` Used in Australia, Cali, Italy
33
What is the U-shaped or lyre trellis?
Developed in France Used in Cali, NZ, Australia cool, Chile, Uruguay Designed for medium to high vigor sites Horizontally divided trellise with shoots trained upwards Good: Open canopy (yield and grape quality) Macine pre pruned Has specific harvester Bad: U needs to be open for leaf and fruit exposure Cost of maintenance
34
What is the pergola system?
``` AKA tendone Overhead Productive system Trunks are 2m high Cane or spur pruned ``` Bad: High construction and labor costs Not good for high vigor sites (shading issues, powdery mildew and botrytis)
35
Timing of vineyard planting prep
Summer: remove existing vegetation and optionals Autumn: Corrective fertilization, deep ploughing (20-60cm) Spring: Deep cultivation, tracing out plantation (making sure straight), planting
36
What are the optional things to do when removing existing vegetation?
Level subsoil (dips can cause water to accumulate) Assess erosion risk and plant trees, dig ditches, etc Break up subsoil at 50-100cm Soil tests to assess nutrient deficiencies (Can increase organic matter content above 2% by adding farmyard manure) Increase pH above 6.5 Disinfect soil (kill nematodes) or leave soil fallow for 5-8 yrs
37
How would you increase a soil's pH?
Use calcite (calcium carbonate), magnesite (magnesium carbonate), or dlomite
38
What compound can be used to improve structure?
Gypsum - reduces dispersion of surface soils
39
Why plough a vineyard site?
Bury existing vegetation, incorporate fertilizers, and increase aeration/drainage, expose large roots
40
What does drainage do?
Makes sure water runs off surface, taken by roots, absorbed into soil particle pores, evaporates from soil, drains down
41
How to improve drainage?
Add manure, organic matter, sand, grit, or lime Ditches (cheapest) Drainage pipes - usually plastic and perforated Mole drainage (used on clay subsoil) - forms cylindrical channel in subsoil Sub-soiling
42
Why terrace a vineyard
If the slope is over 20% - retaining walls are made of grass or stone. Expensive
43
When is best to plant rooted cuttings?
ASAP but wait until spring frost is over. Latest: July
44
How to protect rooted cuttings if not ready for planting?
Keep them in a dark cool place in plastic bags or buckets of water. Prevent drying
45
Why use plastic mulching?
``` No stake No risk of drought no weed competition Soil structure maintained Soil temp increased OVERALL: YOUNG PLANTS GROW FASTER, can gain a year ```
46
What are the disadvantages of plastic mulching?
``` Expense Frost risk Weeds Slugs, mice, snakes Arduous disposal of plastic Superficial rooting ```
47
How to care for young plants
``` Watering Weed control (compete for space) Rabbit protection Slug and snail protection Wind protection Disease protection Tying up and summer pruning (remove flowers and shoots) Replace unsuccessful vines ```
48
What happens if a vine is unpruned
Many short shoots further and further away from trunk Irregular yiels Many small bunches of high acid low sugar berries
49
How does pruning affect shoot size?
More buds = weaker individual vigor = shorter shoots = smaller leaf area
50
How should a vintner balance crop level and leaf area?
High crop + short shoots = over-cropping = high yields of bad fruit Low crop + vigorous shoots = shoots growing too long, detriment to fruit and too much shading
51
Why prune?
Organize plant for maximum light Organize plant for machines without damage Avoid leaf bunching = reduce disease risk and increase quality/yield
52
What are the specs for an ideal canopy?
15 shoots/meter Homogenous 1-1.5 leaf thickness
53
How is a vine's vigor calculated?
The weight of the wood produced in one year
54
Why winter pruning?
Balance fruit and leaf area (depends on yield and quality desired)
55
What is an ideal fruit/leaf vine balance for a shoot with moderate yield?
12-15 nodes long shoot pencil thick | Internodal length 60mm
56
How to calculate how many budes to leave on a vine at winter pruning
Count how many ideal shoots were produced last year Or remove most canes from vine, weigh them, and divide weight by 30-40 More buds in youth and only 5-15% in mature vines
57
What is canopy management?
Organization of shoots, leaves, and fruit to maximise quality of microclimate Impt in cool climate regions and in New World (to curb vigor)
58
What happens when vines are too shaded?
Rate of respiration outstrips that of photosynthesis so leaf consumes rather than produces energy
59
What happens with shaded flowers on a vine?
Lower rates of successful fertilization and fruit set. Higher risk of fungal diseases
60
What to look for when diagnosing canopy management
``` Leaf layer number (aka thickness) Percentage of exposed grape clusters Leaf size/color Presence of lateral shoots Presence of shoot tips growing ```
61
Which viticulturalist did a lot of research into canopy management?
Richard Smart
62
What are Smart's classifications of vineyard sites? What are the proper trellising systems?
High potential/vigor: deep ( >1m)fertile soils, good water supply, high nutrient levels. Generally accepted to have low density (<3000plants/ha) and complex training systems Medium potential/vigor: (.5m-1m) medium deep soils, adequate water, average fertility (3k-5k plants/ha), lyre, Scott Henry, large VSP Low potential/vigor: (less than .5m deep), poor water availability during growing season, low fertility. high density (>5k plants/ha). VSP if sufficient water.
63
Is high vigor or low vigor harder to manage?
High vigor
64
What might cause low vigor sites? Solutions?
Drought stress (Irrigation) Low soil fertility (Increased fertilization, drainage, organic matter) Disease (Diagnosis and treatment)
65
How to fix high vigor issues?
Select low vigor rootstocks Increase water stress in irrigated vineyards Cover cropping in alleys High density plantings (only works in low vigor sites like BDX) Remove alternate vines along the row (reduces shoot vigor and canopy density) Root pruning (Difficult to predict) Retro-fit a more complex system Pinching (Remove select shoot tips around flowering) Shoot positioning, trimming, leaf stripping, crop thinning, green harvesting
66
What kind of grape might use minimal or zero winter pruning? What happens?
Thompson seedless grapes in Australia | Eventually begin to self regulate
67
How does guyot work?
Cane pruned system with one or more replacement spurs Spur buds produce shoots that can be used as canes the following year Single = 1 spur and 1 cane Double = 2 spurs and 2 canes Vine must be planted with straight position
68
What is the main advantage of replacement cane pruning? Main disadvantage?
Limits carbohydrate reserves to control vine vigor (less old wood) Requires great skill, no mechanisation
69
How are the cane and spur selected for guyot?
Spur first Should be closer to trunk than cane Cane shold be further and should be able to be tied down
70
Where do vines grow most vigorously?
At extremeties
71
What is pendelbogen?
Arching the cane upside down to regulate shoot growth | V common
72
What is spur pruning without cordon called?
Bush or head trained vines
73
How is a cordon/spur trained system started?
Cane is tied to the fruiting wire to become permanent wood | Canes coming off of this wood are spur-pruned
74
What is the most common cordon/spur system?
Cordon de Royat: single/double horizontal cordon with shoots vertically trained
75
How are the Sylvoz and Lenz-Moser systems usuallu pruned?
Cordon/spur
76
How are "big vine" systems like GDC usually pruned?
Cordon/spur
77
What are the advantages/disadvantages of cordon systems?
Easier to prune Pre-pruned mechanically More carb reserves (better for frost-risk areas) More vigorous Loss of growing points along cordon (better to keep cordons short)
78
What does a cane with a double bud indicate?
Viruses
79
Which buds are the most fruitful
The ones on the cane formed in the previous year
80
How big must a pruning wound be for it not to heal properly?
Over 30 mm in diameter | not good
81
What is best if larger pruning cuts have to be made?
Leave a short stump that can be cut back following winter
82
What does earlier pruning encourage?
Earlier budbreak - increases risk of spring frost damage | Worries for later budbreak are there too - takes longer to tie down canes
83
What does trimming off shoot extremities do? when does it start?
Controls excess growth and facilitates passage of manpower and machinery, reduces shading and wind damage Reduce canopy thickness Encourage onset of maturity by discouraging competition Aesthetically pleasing Starts in July after last tucking in
84
What is shoot positioning? When should you do it?
Shoot removal, bud-rubbing and tucking in After risk of frost but before flowering
85
Why would a vine shoot be removed?
Badly positioned Too close to the ground Rootstock shoots Too much canopy shade (15 shoots/meter of trellis)
86
How long does it take to do shoot positioning?
17-50 hours/ha
87
What is bud rubbing?
Removal of a potential undesirable shoot before it has a chance to grow.
88
What does leaf stripping do? When is it done?
``` Between veraison and harvest Improve canopy microclimate (quality and health) Improve spray penetration Increase speed of manual harvesting 70hrs/ha ```
89
Why green harvest? When?
Encourage ripening Conform to legal yield requirements Get young vine established Around veraison (too early =increased berry size, too late = no effect bc sugar is already in berry)
90
Which bunches are usually removed in green harvest?
Bunches on laterals and nearest shoot tips By hand 50 hours/ha
91
What is the ideal soil texture?
Loam texture. Can’t do anything i achieve it
92
Where do macronutrients exist in the largest quantities?
Plant tissue (.2 to 3% of dry weight)
93
What deficiencies cause chlorosis? How can you tell?
``` Iron Nitrogen Magnesium Sulfur Yellowing of foliage ```
94
What does nitrogen deficiency do?
Chlorosis Reduced vigor Smaller leaves and shoots
95
What does potassium deficiency do?
Older leaves first White varieties become yellow Red varieties become red Uneven ripening
96
What does phosphorous deficiency do?
Reduction in shoot growth, reduced fruit set. Red spots
97
What are the macronutrients?
Nitrogen, sulfur, phosphorous, potassium, calcium, magnesium
98
Which macronutrients are rarely lacking?
Calcium and sulfur
99
What does magnesium deficiency do?
Yellowing between veins for whites and reddening for reds
100
What does iron deficiency do?
yellowing of leaves
101
What does maganese deficiency do?
Yellowing between veins
102
What does zinc deficiency do?
Little lead symptoms
103
What is a petiole
A stalk that joins a leaf to a stem
104
What deficiences might affect vine performance without showing symptoms?
Magnesium and sinc
105
How often is soil analysis conducted?
Every 2-3 years
106
Why isn't pre-fertilizing used for nitrogen?
High level of mineralisation of organic matter and nitrogen's high mobility
107
What nutrients are important to balance?
Mg v Fe N v K Mn v Fe
108
When are P and K added? when is N added?
P/K: fall | N: spring
109
What are the pros and cons of organic soil?
``` Pros: Can be free or cheap High in humus (soil structure and water retention) Soil aeration and organisms Slow release ``` Cons: Bulky Need to be incorporates into the soil
110
What are the main formats of organic fertilizer?
Farmyard manure Slurry or ceral straws Cover crop (ie: white mustard, leguminous crops like vetch) Foliar fertilizers (good for nutrients that might otherwise be immobilised in sooil)
111
What are the pros and cons of weeds?
``` Pros Prevent soil erosion Prevent nitrate leeching Biodiversity Reduce vine vigor Soil structure Warning of diseases ``` ``` Cons Competition for water and nutrients Smother aerial parts of vine Machinery and personnel hampered Frost risk Pests and diseases Not pretty ```
112
What are the main methods of weed control
Cultivation Ground cover Herbicides Mulching Other: Animals. Flame weeding
113
What is cultivation?
Controls weeds In autumn, ridge soil up under row. In spring, de-ridge it back to the center. don't do it too much to preserve soil structure ``` Good: Effective Efficient than fertilizers Decrease compaction Protect trunks against cold Favors deep root development ``` Bad: Only lasts for a little (increases weed germination)
114
When are cover crops best sown?
Autumn. | Gaining popularity in low density high mechanised vineyards
115
What types of herbicides can be used in a vineyard?
Pre-emergence herbicides (apply before budburst, inhibit photosynthesis in young seedlings) Contact herbicides (absorbed through green organs - temporary effect in well established root systems) Systemic herbicides (absorbed through leaves. In sap. Destroy whole plant. Slow acting. Use after leaf fall.)
116
How does mulching work?
Spread matter onto soil to suppress weeds by restricting access to light.
117
What types of mulches are usedful?
high carbon nitrogen ration (straw paper woodchip) on vigorous plants Higher nutrients (mushrooms, manures) on poor growth Deeper reduce soil moisture Organic = earthworms = waterlogged areas
118
What types of irrigation may be used?
Flood, sprinkler, drip, deficit
119
How does flood irrigation work?
Fed from a supply canal and run down rows. Common in Argentina ``` Needs: Lots of water Flat slope Low cost high labor Not as efficient Infrequent ```
120
Pros/cons of sprinklers
Wasteful of water Could cause runoff and erosion Good at preventing frost Fungus
121
Pros/cons of under-canopy systems
Leaky hose or sprinkler or microjet High level of management bc of blockages Machines could damage
122
Drip systems
Each vine has a plastic dripper | Expensive to install
123
What is a controlled deficit and why is it good/bad?
Mild water stress Good during the ripening phase Restrains vegetative growth
124
What is regulated deficit irrigation?
Developed in Australia Controls growth in order to increase quality Deficit applied between fruit set and a month after veraison not advised for very hot regions
125
What is partial rootzone drying?
Controls vigor and maintains wine quality Half of the root system should always be in a dry or drying state Alternated on a 10-14 day cycle
126
What are the major pests in vineyards?
Viruses Phytoplasmas (small bacteria without cell walls) Bacteria Fungi Nematodes (unsegmented parasitic or free living roundworms) Arthropods (segmented invertebrates - spider mites, grapevine moths, phylloxera, leafhoppers, cicadelles) Vertebrates Weeds
127
What are the different pest management philosophies
Prescriptive Reasoned pest control (lutte raisonee) Integrated pest management
128
Powdery mildew: what is it, effects, and treatments
Oidium - Fungus Introduced in 1800s Damages the young green parts of the vine (leaves curl, develop dull grey patches with cobweb patches. berries are covered in grey/white fuzz snd drop off) Can be spread by wind Doesn't like bright sunshine Doesn't need rain to germinate, just shade and humidity Prominent in warm, cloudy but not rainy summers with humid microclimate Treatments: Sulfure sprays prevent, stop, and cure it Better to prevent at bud burst DMIs can be used as they penetrate into green tissue (can become resistant)
129
Downy mildew: what is it, effects, and treatments
Peronospora - Fungus Lives IN vine tissue not on top Damages green parts of plant. Yellow oil spots on leaf, white downy patches on underside Leaves fall off Flowers can fall ooff Berries go grey then brown and dried Needs rainfall and warm temps Happens in rainy winters, springs, and stormy war summers Treatments Reduce leaf bunching (canopy mgmt) controls Copper salts pesticides are preventative, before rains
130
Grey rot: what is it, effects, and treatments
Same as Botrytis - Fungus Found in plant debris, can be parasitic Needs high humidity and warmth Enters through wound Produces enzymes that break down plant tissue and cause it to brown mostly attacks leaves (grey fuzz) and berries Berries become brown and sensistive skin Entire bunch usually Prevention is key (hard to treat) Use broad spectrum fungicides Spray at flowering, berry set, bunch closure, veraison, befor eharvest
131
Botrytis: what is it, effects, and treatments
Grapes should be kepy healthy until 7% potential ABv has formed in grape Lilac skin If rainfall before harvest = develop into grey rot instead
132
Mites: what is it, effects, and treatments
Arachnids tiny Feed on green parts of vine, esp leaves Can winter in buds or bark and lay eggs in spring Sulfur sprays Predatory mites Miticides in summer Species: Red spider mite Yellow spider mite
133
Eutypa dieback: what is it, effects, and treatments
Dead Arm - Fungus SE Australia, Califonria, SW france, SAfrica ``` Fungus enters pruning wounds Blocks and kills water conducting tissue Not in young vineyards Stunted shoots, small yellow leaves Yield loweres ``` Replace vine or train a healthy shoot to replace Control with hygeine
134
Fanleaf virus: what is it, effects, and treatments
Virus Shoot growth malformed with double nodes, short internode, zigzag, distorted leaves (look like fans and yellow veins) Small bunches with poor fruit set, millerandange = 80% reduction in yield Worsens over time (Cab Sauv) Spread by infected material No cure
135
Leafroll virus: what is it, effects, and treatments
Most widespread grapevine disease Autumn: red and yellow leaves with rolled edges Reduces yield by 50% and sugar by 30%, weaker wines Infected material Mealybugs No cure
136
Grape moths: what is it, effects, and treatments
``` Larvae mostly damage the vines Light brown apple moth European berry moth Grape berry moth Feed on foliage and bunches and open wounds Natural enemies, insecticides ```
137
What temperatures harm a vine after budburst?
under 0C
138
What training systems can reduce frost
High wire systems | Geneva Double Curtain
139
How do fans and windmills help? How many?
Mix the cold air near vines with warm air above. Permanent = 1/6-8ha, moveable = 1/4ha
140
What are some examples of wind breaks?
Artificial: mobile structures Natural: Must be planted ahead of time, twiggy trees Crop should be within 10x the height
141
What are some preventative hail measures?
Explosive rockets that instigate rain with iodide Towers with static electricity to divert thunderstomrs Netting
142
What are some major vineyard hazards
``` Excess rain Drought Hail Wind Frost ```
143
When did viticulture start using agrochemicals? What was used prior?
1950s | Before: sulfur and copper, manure
144
Are synthetic agrochemicals allowed in integrated viticulture?
YEs, but encouraged to monitor vineyards and only use when needed
145
What are some principles of integrated viticulture?
Reduce chemicals Establish green cover in higher precipitation areas Balance growth and yield and enable sunlight Ventilate canopy Conserve soil quality Irrigation only when needed International Organization for Biological Control
146
Who regulates organic viticulture?
International federation of Organic Agriculture Movements from 1991
147
What is the Bordeaux mixture
A fungicide containing copper sulfate and calcium oxide
148
What are two biodynamic preparations?
Horn manure 500 -Cow dung is placed in a cow horn and buried over winter. Also sprayed 2-4 times throughout year All about the soil HOrn silica (501) -Finely ground silica is placed in a cow horn and buried over summer - energized by sun -Improves photosynthesis Encourage strengthening against fungal and insect attack
149
What is the limit of Bordeaux mixture for biodynamic wineries?
3kg/ha per year