Viticulture Flashcards
(140 cards)
1
Q
What are the 3 main types of acid found in wine?
A
Malic Acid
Lactic Acid
Tartric Acid
2
Q
What is Achéria?
A
The oldest name/most primitive clone of Cabernet Franc, originating in Basque Country
3
Q
Where did Gewurztraminer originate?
A
Despite the German sounding name, Gewürztraminer is Italian in origin, and is thought to be indigenous to the Alto Adige region of northern Italy. The prefix “gewürz” means spice in German, though the meaning is more along the lines of outrageously perfumed than anything that might come out of a kitchen spice rack. The grape is not actually a distinct variety but rather a pink-berried, highly aromatic clone of Savagin, one of the ancient so-called “founder varieties.”
(Karen McNeil)
4
Q
Pelaverga
A
There’s only about 20ha in the world planted, most concentrated in the village of Verduno.
Light tannin, sappy red fruit, peppery spice - a very easy-drinking red.
-Burlotto
-Castello di Verduno
-Fratelli Alessandria
5
Q
What is the name of Gamay’s teinturier mutation?
A
Gamay de Bouze
6
Q
Viviser
A
An old name for Chasselas, used in and around Baden
7
Q
PIWI
A
Pilzwiderstandsfähige Rebsorten: Fungus-resistant grape varieties aka HYBRIDS
* associated with Germany
* adaptability, sustainability
8
Q
What is the French term equivalent of PIWI?
A
ResDur (Résistances Durables - a program started in 2000)
9
Q
Scion
A
the above the ground portion of a grafted vine
10
Q
Canes and spurs
A
canes = shoots grown in previous season that have lignified/turn brown. 1-4ft long after pruning
spurs = canes trimmed to a few inches
11
Q
Cordon
A
Permanent horizontal extension of the trunk with a number of spur positions located along them
12
Q
Vitis vinifera’s parent species?
A
Vitis Sylvestris
(both belong to family Vitaceae)
13
Q
Canopy
A
refers to all vegetative growth that occurs during the growing season
14
Q
Suckers
A
shoots sprung from dormant buds on older wood - do not usually produce fruit and are typically removed earlier in spring
15
Q
inflorescences
A
flower clusters that resemble immature grape clusters. Appear in the beginning of the season
*initiated during the previous growing season
16
Q
Rachis
A
The stem holding the cluster of potential grapes
17
Q
Ampelography
A
The science of identifying grape varieties based on morphology
- clusters/berries shape & size
- leaf characteristics
- overall growth patterns
18
Q
Xylem
A
Carries water and nutrients from roots throughout the vine
19
Q
Phloem
A
carries sugar from the leaves throughout the plant
20
Q
ATP
A
adenosine triphosphate: usable energy created through respiration, occurs in every part of the plant including roots both day and night. Uses oxygen, releases CO2
21
Q
Photosynthesis
A
Plant takes in CO2 through stomates (microscopic pores in leaves)
*releases water through stomates (transpiration)
*stomates close during periods of stress to conserve water - stops photosynthesis and slows respiration
22
Q
Vine Vigor
A
refers to vegetative growth produced by the vine. Assessed by:
*shoot length/diameter
*number of shoot’s per vine
*tendency to produce laterals/suckers
Quantified by pruning weight - material removed
Excessive growth is bad for quality/quantity. Too much energy to canopy, not enough on fruit development.
Too much canopy = not enough light, buds aren’t as productive and are more disease prone
23
Q
Ravaz Index
A
A measurement of vine balance: considers ratio of fruit weight to pruning weight
*healthy range is 4 to 10
24
Q
3 common rootstock species
A
Vitis rupestris
Vitis riparia
Vitis berlandieri
25
2 main genus of family Viticeae?
Vitis
Muscadinia
26
Crossing vs Hybrid
the offspring of 2 varieties belonging to same species (Riesling etc)
Hybrids are interspecies crossings
27
What species of grape vine typically shows foxy aromas?
Vitis Labrusca
28
Proles Pontica
3 main proles (Pontica, Occidentalis, Orientalis) - primary centers of cultivation
Aegean/Black Sea
Vermentino, Zin, Furmint, etc
*jagged leaves, white hair underside, midsized clusters & small/med berries
29
Proles Occidentalis
3 main proles (Pontica, Occidentalis, Orientalis) - primary centers of cultivation
Western Europe
Chard, Riesling, Pinot,etc
*convex leaves, small compact bunches, small round berries
30
Proles
Proles (latin) = scion, offspring; grape variety classification by Dr. Negrul
**Orientalis**: Caucasus; Cinsault, Muscat
**Pontica**: E. EU; Harsevelu, Furmint, Clairette
**Occidentalus**: IT, FR, etc. Chard, Merlot, etc
31
Tannin expression related to moisture
Water stressed grapes = more tannin
*even after accounting for berry size
32
Monoterpenes
compounds responsible for flavors of rose, lychee, and orange blossom
33
Clones
Variants within a grape variety that differ slightly in terms of morphology or behavior
*mutations are caused by errors in cell division and genetic variation is the result
*viral infection affects gene expression - another source of mutation
(all of the Pinot's are technically clones of Pinot Noir; Gewurz is a genetic mutation of Sauvignon Blanc)
34
Give 3 examples of American hybrid varieties
Clinton
Catawba
Delaware
Herbemont
Isabella
Niagara
Noah
Norton
Purpose of American hybrids was to adapt to fiercely cold winters and hot disease-prone summers
35
Give 3 examples of French hybrids
Goal was to resist pests and diseases around time of phylloxera and downy mildew. Covered 1/3 of French vineyard by 1950's.
Baco Noir and Blanc
Chambourcin
Chancellor
Couderc Noir
Marechal Foch
Plantet
Villard Noir and Blanc
Seibel
Seyval Blanc
Vidal Blanc
36
Vitis Riparia rootstock
- downfalls
riparia = native to riverside areas. Shallow fibrous roots.
*not drought tolerant
*does not do well in lime soils
*low vigor, earlier ripening
37
Vitis Rupestris rootstock
Shrubby vine native to American South
* loves rocky creek beds and low-nutrient soils
* extensive root system is good for drought tolerance and searching for water
* vigorous; large canopy on fertile soils
* tolerant of nematodes/viruses
Ex: St. George
38
Vitis berlandieri rootstock
Native to Texas and deep limestone soils
* good choice for alkaline soils
* deep roots = some drought resistance
* later ripening, variable phylloxera tolerance
Does not root from dormant cutting - so all rootstock from this species will never be pure belandieri
39
EU Climate Zone A
Ex: Germany (except Baden), Austria, Loire, Champagne, Alsace
Can adjust alcohol levels up to 3%
Can deacidify - cannot acidify
40
Köppen-Geiger
Climate classification
5 main groups:
tropical, dry, temperate, continental, polar
* further divided based on temp and precipitation patterns
41
Vine growth occurs in what temperature range
50 to 95º F
(mid-70's is optimal)
42
Winkler Index
Categorizes viticultural areas with similar accumulation of “growing degree days” from April 1 to October 31
*(daily avg temp - 50ºF) for every day 4/1 - 10/31 is totaled up
43
How many leaves does it take to ripen a cluster?
12 - 16
44
Min. # of sunshine hours/year to ripen Vitis Vinifera?
1250 hours
45
General latitude range for growing vines?
30 to 50
46
Inversion layer
An imaginary boundary which cold air is trapped under a layer of warm air
*causes frost events
47
Methods to mitigate frost
- site selection: cold air settles in low-elevations; bowls with no means of draining air are especially frost prone
- varietal selection: don't plant early budding varieties in frost prone places
- air circulation: mow cover crops
- sprinklers: water freezing can warm the vines a few degrees; constantly applying water during frost event
- Heat: smudge pots, small fires
- Pruning methods: leave a long spur or prune late to use "sacrificial buds"
48
At what temp do dormant vines risk freeze damage? Mitigation methods?
5ºF and below. Most can survive to 0 but most risk death if they go below
1. burying the canes or the base of the vine
2. geothermal, geotextile blankets
49
Hail prevention?
Netting or canyons to disrupt air patterns
50
Drought friendly rootstock?
St. George, 110R, and 140R
51
Sunburn mitigation techniques
1. clay-based "sunscreen" on fruit/canopies (Australia)
2. shade clothes around fruit zone post veraison
3. sprinklers/misters for evaporative cooling
52
Loam
Soil texture comprised of a blend of different particle sizes, including sand, silt, and clay
53
Alluvial
Soil transported and deposited by (non-marine) surface water. Alluvial deposits have been cemented into rock
54
Colluvial
soil transported by gravity or erosion
55
Fluvial
Soil weathered, transported, and deposited by rivers and streams
56
Calcareous
Alkaline soil with a high proportion of calcium or magnesium carbonates
- cool, good water retention
- lower temps = delay ripening
- Agrillaceous = calcareous clay
57
pH
is a scale of acidity that ranges from 0 (very acidic) to 14 (very basic), with water considered neutral at a pH of 7
*Soils described as acidic have a pH below 6.5, neutral soils are 6.5 to 8, and alkaline (basic) soils are over 8
58
Alkaline soil types
pH 8.5 or higher = alkaline
calcareous soils including limestone, chalk, tufa, marlstone, and marble
59
Acidic soil types
asalt, sandstone, shale, slate, and schist tend to be more acidic
60
Most important soil-derived nutrients for a vine?
nitrogen
phosphorus
potassium
(macronutrients)
61
6 soil-derived macronutrients important to viticulture
Nitrogen
phosphorus
Potassium
sulfur
calcium
magnesium
62
Nitrogen
Controls growth and development. The most significant thing for development, quality and yields.
*deficiency: low vigor; chlorosis in older leaves
63
Phosphorous
- purpose
- what causes deficiency
Required for energy transport and storage
*deficiency is rare except on acidic soils. Low yields, yellow and red patches
64
Potassium
Regulates water movement in and out of cell, essential for deacidification during ripening, important for red color development
*deficiency = low yields, low pH
65
Calcium
Maintains integrity of vine's structure
*deficiency is rare except on acidic soils
66
Magnesium
Component of chlorophyl. Important for photosynthesis and ripening.
*deficiency = reduced sugar accumulation in fruit
67
Chlorosis
Yellowing of the leaves along the vein or inside the leaf margin. Negatively affects quality of canopy shade.
Caused by:
1. nitrogen deficiency
2. iron deficiency
3. lime heavy soils
68
Why are grapevines not propagated from seed?
DNA is recombined during fertilization; vines grown from seed might have some things in common with parent vine but will basically be a new variety with little in common.
seeds of self-pollinating vines are highly inbred and prone to recessive-type diseases; many are nonviable or non-fruiting
69
Clonal Selection vs Massal Selection
Clonal = cutting from a single parent vine. The goal is to replicate the traits of that vine across the vineyard. Might create a more even, easy-to-manage vineyard
Massal Selection = cutting taken from multiple plants across vineyard that may have undergone small mutations.
** Increased genetic diversity, possibly more disease resistance; potentially, more wine complexity
70
Provignage
- method
- examples
Traditional propagation method.
* a shoot from a grown vine is laid down into the ground, where it roots and forms a new vine that may be separated from the mother vine
* cheap, "easy", but can only be done in phylloxera-free soils
Ex: Bollinger's Clos Chaudes Terres and Clos Saint-Jacques for Vieilles Vignes Francais
71
Bench Grafting
Bench grafting: dormant rootstock and scion are grafted together at nursery, usually by machine.
* Graft wound is wrapped and stored in warm humid room to callus for a few months. Then sealed with wax and stored in cold room until ready to plant
OR
* planted in a pot after callusing, grown in greenhouse, and sold as green-growing bench graft aka potted vine (less expensive, mature 1 year earlier than dormant bench grafts)
72
Field Grafting
Rootstock is planted and grows for a season. Scion is grafted on top either in fall or following spring.
*chip-budding: very small pieces of the cutting and one bud are inserted into the rootstock
73
Chip-budding
Very small pieces of cuttings containing a single bud are inserted into the rootstock
*done during field grafting as the scion is being grafted onto the planted rootstock
74
2 methods of grafting vines
Field grafting: happens in the field; more expensive - but cost is spread over two intervals. Requires skilled labor, has higher failure rate, but vines have a more stable root system at time of grafting and may have more longevity
Bench grafting: happens in the nursery; easier, less expensive, and only successful vines are planted
75
FPS
Foundation Plant Services
*the major US nursery to legally import cuttings. They must certify that the cutting is pest/disease free
76
Row Orientation
N-S: both sides of vine subject to equivalent duration of sunlight throughout day. BUT west side fruit may be subject to more afternoon heat
E-W: canopy intercepts max amount of sunlight all day but very different exposure on north vs south side of vine
NE-SW: modern method for warmer regions - max light interception + ideal shading during hottest parts of day
77
Modern vineyard architecture for warmer regions?
NE-SW: modern method for warmer regions - max light interception + ideal shading during hottest parts of day
78
Typical yield from 1 ton of fruit
120–160 gallons of wine ≈ 50–70 cases
79
J-rooting
common cause of young vine decline; happens when vines are planting with their rootstock bent upwards
80
Cordon-trained
Cordon-trained, spur-pruned
*1- 4 cordons attached to trunk with regular permanent spur positions
*shoots grow from spurs each season - then are trimmed back after harvest
* Vine looks identical season after season
PROS: good for warmer regions; easy, fast, cheapest to prune; even shoot development, clear fruit zone; more permantent wood = better nutrient, water storage
CONS: more vigor = wider spacing; takes extra year to establish; not good for varieties like Nebbiolo/Carmenere that have low fertility in bud close to cordon; buds push at same time so can be risky for frost
81
Kicker Canes
Sacrificial canes; method used for spur-trained vines to mitigate frost risk and control vigor
* kicker cane shoots will go through budbreak 1st bc they were there 1st.. delay budbreak in the remaining spurs then removed after risk passes
82
Head-Trained, Cane-Pruned
Ex: Guyot
1 spur for each fruiting cane attached directly to the head - called replacement/renewal spurs
* shoots form on each bud along spur/cane
* the grower selects a new fruiting cane (the baguette) and lays it down during pruning to be next year's cane - removing the cane from the previous season
83
Baguette (pruning term)
Applies to head-trained, cane-pruned vines - the new fruiting cane that will be laid down during pruning to produce fruit the following year, while the grower cuts back the previous year's cane
84
Pros and cons of cane-pruned vines
PROS
* less permanent wood & fewer reserves = more suited for high density plantings
* more productive than spur-trained vines
* fewer pruning cuts = less prone to fungal diseases that enter through pruning wounds
CONS
* requires skilled pruning labor
* not suitable for mechanization
* budbreak and development are uneven along the cane
* susceptible to winter freeze since buds are further from permanent wood
85
Head-trained
- type of pruning
- examples/explanation
- pros and cons
Spur-pruned
Ex: bush, gobelet
No trellis. Many spur positions on arms that form the vine's head. Spur positions are restored at pruning
*typical to warm, dry places with limited water availability
*cost effective - no trellis/wires to manage. Canopy work is minimal. Pruning becomes easier over time.
However..
*least productive, cannot mechanize. bunches are prone to crowding
86
Sylvoz
Cordon-trained, cane-pruned
*used on high yielding varieties/sites
* large number of fruiting shoots during the growing season
87
What happens when you train vitis vinifera downward?
Vitis vinifera likes to grow vertically - training downward is a method to devigorate
88
VSP
Vertical Shoot Positioning
*non-divided canopy, 1 fruit zone
* shoots are trained vertically and compressed into a single wall
*ideal for high density plantings
*works well for lower vigor vines. Good light interception, good airflow, good for anti-fungal spray coverage
Canopy on higher vigor vines may become too dense/humid. A spreader bar might be used to spread canopy and give fruiting zone space
89
California Sprawl
TRELLIS SYSTEM
2-wire system: fruiting wire, foliage wire. Shoots grow up and sprawl over foliage wire. Self-shading, dense canopy, simple and mechanizable
Typical in CA Central Valley's high-yielding vineyards. Suitable for hot climates.
90
Divided Canopy Trellis System
Good for high vigor sites. Spreads out the canopy to provide more space and avoid crowding. Multiple fruit zones = sometimes uneven ripening
Ex: Lyre, Geneva Double Curtain, Wye, Scott Henry, Smart-Dyson
91
Pergola
Good for high vigor, high production varieties
* max. light interception + max. fruit zone protection
* good airflow = reduces fungal pressure in humid areas
92
1st event of the growing season?
Budbreak - happens when temps near 50º
débourrement
93
Weeping
Occurs during budbreak as sap is being transported from roots to buds to initiate shoot growth after dormancy.
Weeping = sap is being pushed through pruning wounds during this process
94
What does it mean for buds to "push"
During budbreak - compressed shoots stored inside the buds start to grow
*buds located further from the ground push first (apical dominance)
95
Timeline for bloom?
occurs 6-8 weeks after budbreak; lasts 1-3 weeks
96
Fruit Set
Fertilized flowers turn into berries. First glimpse of season's possible yield. May/November
*1/3 of flowers turn into berries in favorable circumstances
* couloure occurs here - due to carbohydrate imbalance in vine, or bc berries simply fall off or fail to set properly
97
Coulure
Shatter: large amount of berries are unsuccessfully fertilized and few berries form
*cold weather and varietal tendencies are to blame (Merlot, Grenache susceptible)
[other irregular outcome:
Hen and Chicken: berries contain different numbers of seeds resulting in differing berry size - often result of nutrient deficiency and stress. Detrimental to yields but not necessarily to quality]
98
Millerandage
Hen and Chicken: berries contain different numbers of seeds resulting in differing berry size - often result of nutrient deficiency and stress. Detrimental to yields but not necessarily to quality
[other irregular outcome: Shatter: large amount of berries are unsuccessfully fertilized and few berries form
*cold weather and varietal tendencies are to blame (Merlot, Grenache susceptible)]
99
Veraison
Berry colors change. 4-6 weeks post flowering. Vine switches from growth and development to focus on fruit.
100
When does pruning occur?
during winter dormancy and before budbreak
(December and March)
101
Spur-pruned
short permanent fruiting positions ("spurs") are maintained on a main structural arm (cordon, cane).
Annual renewal: each year, the spurs grow shoots & fruit. They harvest and are pruned back.
102
Cane-pruning
Buds that grow into fruiting shoots come from a single cane rather than multiple spurs.
*Guyot is a type of cane-pruning
103
Guyot
A cane-pruning method
*producer selects 1 cane that will be kept and used as the fruiting cane the next year (the baguette) and 1 cane is trimmed into the renewal spur
*the cane is bent and tied to support wire - then the rest of last year's growth is trimmed off
104
Cane Cracking
Vine is tied in an arch - good for varieties where the middle buds struggle to push
*Nebbiolo, Riesling
105
Leafing
Removing leaves from dense canopies.
* Reduces disease pressure
* Done anytime after fruit set, but earlier is better.
* oft removed on morning side, left on afternoon side
106
Dropping fruit's effect on ripening?
Dropping fruit speeds up ripening - so in marginal climates, this helps ripen. In warmer places, it leads to uneven ripening as sugar outpaces tannin/flavor development
107
Relationship between large yields and environment
*Warmer climates support higher yields: increased rate of ripening can support more fruit
* larger vines on rich soil can support ripening at higher yields while small vines on weak soil cannot
* higher density = lower per vine yield but higher yield overall
* consider the wine style - acid retention is more important for sparkling and white wines aka higher yields can be more appropriate
108
Cover crop's relationship with frost?
* Bare soil is warmer but cool off faster. Better airflow
* Cover crops are cooler during day but take longer to cool off at night since airflow is impeded
* cold air can be trapped in tall cover crop = frost risk. Mowing after budbreak mitigates that
109
Cover Crop Benefits
Goal: optimize water / nutrients avl to the vine, limit erosion, build soil organic matter, influence microclimate
*legumes add nitrogen to soil
*brassicas control nematode population
* grasses with high water requirements devigorate via competition
* limit winter erosion, mitigate compaction, soak up excess spring moisture
110
Pros and cons of tilling
Turning over of top 6 - 10in
*PROS: add fertility to soil through green manure, reduce competition between vine and cover crop, reduce rodent population
*CONS: encourages erosion, destroys soil structure, disrupts soil microbial communities, brings carbon to the surface
111
Mulching
mowing or crimping cover crop to create a "carpet" over vineyard that discourages weeds from growing
*helps conserve moisture, cool ground temp, and encourage soil bacteria
112
Alternatives to herbicide
1. Low-growing perennial cover crop like clover that outgrows weeds
2. Mechanical cultivation - French plow or other implement that scrapes top of soil to remove weeds/plants
113
Phylloxera
Phylloxera Vastatrix
*yellow root louse
*feeds on vine roots. Creates punctures that allow soil pathogens to infect, causing necrosis and prevents healthy uptake of water and nutrients. A slow death.
*doesn't like sandy soils/places that flood (incl. flood irrigation)
114
Nematodes
Feed on roots, eventually disrupting water and nutrient uptake
*Dagger nematode: vectors fan leaf virus
*certain cover crops (Mustard) are toxic to them; leaving land fallow for several years helps
115
Mealybugs in the vineyard
Vector leafroll virus
(Dagger nematode vectors fan leaf virus, glassy-winged sharp shooters = Pierce's disease)
116
Glassy-winger sharpshooters in the vineyard
Vector Pierce's Disease
(Dagger nematode vectors fan leaf virus, mealybugs vector leafroll virus)
117
Methods for insect infestations
*relocate host plant outside of vineyard to divert insects
*ladybugs to feed on immature aphids and leafhoppers
* pheromones for mating disruption
* and... pesticides
118
Wildlife prevention in the vineyard
*bird nets
*fencing
*early ripening "sacrificial" varieties
* noise emitters
* Scarecrows
119
Powdery Mildew
Oidium (Erysiphe necator)
Fungus - prefers damp 70 -85ºF to spread. Spreads via wind
*detrimental from budbreak to veraison
*treated with systemic fungicides or sulfur sprays, BDX mixture
*Serenade, Sonata = organic biological fungicides
120
What are Serenade and Sonata?
Organic biological fungicides
* treats oidium
121
Downy Mildew
Mildiou in French (Plasmopara viticola)
*prefers 65 - 77º. Only spreads through water... so places with rainy growing seasons are naturally more susceptible
* cripple shoots and leads to defoliation which shuts down the vine
*treatable with Bordeaux mixture
122
Botrytis-susceptible varieties?
Spores get trapped in tight bunches during bunch closure. Dense, shady, humid canopies foster disease.
Tight bunched varieties: Chard, Riesling, Pinot, Zin, Chenin, Sauv Blanc
*many red varieties have compounds that fight botrytis in skins
123
Eutypa Dieback
Caused by Eutypa Lata. Trunk disease, fungal spores enter through pruning wounds.
* affects a single spur position before moving through vine
* stunted shoots, shriveled fruit, and small, cup-shaped, chlorotic leaves
124
Esca
Trunk disease, fungal spores enter pruning wounds
* black measles on berries
* distinct tiger-striped leaves with scorching along the margins
125
Pierce's Disease
Xylella fastidiosa
*Bacteria. Infects Xylem, prevents transport of water
*vectored by sap-feeding insects like sharpshooters and spittlebugs
*symptoms: delayed budbreak, stunted growth, fruit dehydration, uneven lignification
*vine typically dies in 2 - 5 years
126
Grapevine Yellow
Phytoplasmic diseases
* phytoplams = specialized type of bacteria that infect vine's phloem
* Flavescence doree
* Leafhoppers are primary vector
127
Crown Gall
Bacteria
*infects graft site - galls form at graft union and girdle the vine
128
Examples of viral grapevine diseases
Fanleaf Virus
Leafroll Virus
Red Blotch Disease
129
How long for transition from conventional to organic certification?
Min. 3 years
130
Biodynamic certifications?
Demeter
Biodyvin
respekt-BIODYN
131
Regenerative Farming
Next frontier of organic farming.
Beyond "do no harm" - actively improving the land through soil building, nurturing microbial ecosystems, and advancing the health of the vineyard
**ultimate goal is to reduce climate change through carbon sequestration
**focus is on management of the vineyard floor
132
Examples of Sustainable Certifications
Sonoma County Sustainable
Napa Green
Lodi Rules
SIP Certified
LIVE
Porto Protocol
133
Integrated Pest Management
* exploits predator-prey / host relationships habitat manipulation
* physical barriers
* biological interventions like mating confusion
134
Suckering
Removing weak, sick, or poorly located vine shoots that grow from latent buds on the trunk and cordon
135
French term for pruning
taille
136
French term for rootstock
porte-greffe
137
shot berries
Small, hard, green berries that contain no seeds
138
Biodynamic Preparations
BD500, BD501, BD508 are field sprays
BD502 - 507 are compost treatments
500: manure
501: silica paste
502: yarrow flowers
503: chamomile flowers
504: stinging nettles
505: oak bark
506: Dandelion flowers
507: Valerian flowers
508: Horsetail Plant
139
"Active lime" in calcareous soils
Portion of the soil that is highly reactive - readily dissolves and participates in chemical reactions in soil
* increases soil alkalinity
* more alkaline soils = nutrient deficiencies, chlorosis, reduced vine growth & yields
* very dry soils
140
French term for MOG
Corps Etranger
