Viniculture and Viticulture Flashcards
Phomopsis viticola is a simlar (but separate fungus) disease to what?
Eutypa Dieback
What is Esca commonly known as? What is unique about this fungus?
- Black Measles
- This is a result of a complex of fungi, rather than a single organism
What is Bordeaux Mixture? When was it developed?
- CuSO4 + H2O + Lime
- 1885
Symptomatically, what diseases are like viruses?
Phytoplasma
What fungul diseases affect vineyards?
- Powdery Mildew
- Downy Mildew
- Eutypa Dieback
- Esca
- Black rot
- Bunch rot
In what order do these occur: harvest, fruit set, budbreak, veraison, flowering?
Budbreak, flowering, fruit set, veraison, harvest
What is a VSP trellising system?
Vertical Shoot Positioning - may be used for either cane- or spur-pruned vines
What is soutirage?
Racking
What is a chapeau?
Cap
What virus diseases are affecting vineyards?
Leafroll
Fanleaf Degeneration
Rugose wood complex
What is pigeage?
Punching down
What low temperature will not allow yeast to work? What high temperature kills most yeast?
- 50ºF
- 113ºF
What bacterial diseases affect vineyards?
- Pierce’s Disease
- Crown gall
- Bacterial Blight
What are MOG and “jacks”?
- MOG = Material Other than Grapes
- Jacks = stem pieces left in grapes
Vines prefer what temperature range? What is the ideal temperature?
Prefer - 50-68ºF
Ideal - 57ºF
What remontage?
Pump over
What temperature can red wine fermentations reach? What temperature causes risk? What are the risks?
- Red wine ferm.= 90+ºF
- Risk = 95ºF - may cause volatized flavors or stuck fermentations
Where is the Tendone trellising system commonly used? What is it called there?
- Italy - Pergola
- Portugal - Enfrocado
What disease is responsible for as much as 60% of the world’s grape production losses?
Leafroll virus
What are the four broad categories of vine disease?
- Fungal
- Viral
- Bacterial
- Phytoplasma
What does “san soufre” indicate?
“Without sulfur”
How long does flowering occur? What is occuring during flowering?
- 10 days
- Self-polinating - begins the process of fertilization
What are the vulnerabilities during flowering?
Cold, frost, and wind
What temperatures do red and white grapes prefer to ripen successfully?
Red ~ 70ºF
White ~ 66ºF
What is délestage?
The wine is racked into a separate vessel, emptying the one with the cap, and then pumped back over the cap
Viticulture is restricted to what temperate bands of latitudes?
30º-50º
What trellising system is preferred for Pinot Noir in Champagne?
Cordon de Royat
How long is traditional Nebbiolo post-ferment macerated?
at least a month
What is the species of American white oak? Traditionally is it split or sawn? Kiln or air dried?
- Quercus alba
- Sawn - it is less porous, no fear of leakage
- Kiln dried - although many American coopers are using air-drying techniques
What are the ranges for the California Heat Summation Index?
- Region I: 2,500°days F (>1,371°days C)
- Region II: 2,500-3,000°days F (1,372-1,649°days C)
- Region III: 3,000-3,500°days F (1,650-1,927°days C)
- Region IV: 3,500-4,000°days F (1,928-2,204°days C)
- Region V:
When does budbreak generally occur in the North and South hemispheres? What average temp is required? What is the vulnerability?
- North - March/April
- South - Sept/Oct
- As the mean air temp surpasses 50ºF
- Vulnerability - frost
What is a “nepovirus”? Which nepovirus is a concern today?
- A nepovirus is a virus spread by soil nematodes feeding on infected roots
- Fanleaf Degeneration
When do the vines start bleeding water sap from the pruned canes?
February (N Hemi) or August (S Hemi)
What is collage?
Fining
What are anthocyannins?
Color compounds
Why are off-dry and sweet whites often filtered?
The sugar can lead to unexpected refermentation in the bottle
When does flowering occur?
6-13 weeks after initial budbreak (Depends on the climate)
What are the 3 stages of barrel making?
- Chauffage (warming)
- Cintrage (shaping)
- Bousinage (toasting)
T o F - A grape cluster is the effect of a single fertilization during flowering.
False - each grape is the product of individual fertilization
Describe the Cordon de Royat system?
- Spur-pruned/cordon-trained
- Similar to Guyot system w/a single-spur pruned cordon extending horizontally from the trunk, rather than a 2 year old can
What is the most common bunch rot?
Botrytis bunch rot
What is “grapevine yellows”?
Another name for phytoplasma diseases
What is microbullage?
micro-oxygenation
What are the treatments for Downy Mildew?
Bordeaux Mixture
When does veraison generally occur? What is happening in the vine?
- August (N)/February (S)
- Sugars are moved from the leaf system to the fruit
What is “sulfites” vs “sulfides”?
- SO2 = sulfites
- Sulfides = H2S, mercaptans, and other foul smelling compounds produced under reductive conditions
- H2S levels may also be affected by the addition of SO2