Viticulture Flashcards
spurs develop into..
canes
a cane that is retained from season to season will become a…
cordon
How is a clone made?
cut off short length of young cane and place it into water. it will begin to grow roots, then plant it
what is field grafting?
grower removes branches of grape vaine, and then insert a cutting from desired vine.
it is said that a vine begins producing optimal fruit after ___ years
6
harvest in the northern and southern hemisphere takes place about ____ months apart
6
what is “weeping”
beginning of growth cycle - sap flows up from the trunk and out the tips of the canes - precursor to budbreak
what happens once leaves develop?
photosynthesis can begin
next crictical step of growth cycle after budbreak and when does it occur
flowering - 40 to 80 days post budbreak
the transition from flower to berry is called..
fruit set
this malady can cause poor fruit set
coloure
what is millerandage?
malady that results in bunches that have a lot of small, seedless berries
what is veraison?
sudden acceleration of maturation
when does harvest take place, post veraison?
6 to 8 weeks
grapes need to reach both ______ (Sugar) maturity and ____ maturity
physical / phenolic
period of time from bud break to harvest is typically…
140 to 160 days
what happens during photosynthesis?
carbon dioxide and water is converted to sugar
ideal temp range for photosynthesis?
50 - 95 - slows below and above that
what process if responsible for the loss of malic acid in grapes?
respiration
what is respiration?
the process of the vine breaking down its sugar and other carbs for energy
why do cool nights help preserve acidity?
the vine will break down its malic acid at night in a process called respiration. the cooler the weather, the slower the rate of respiration, and vice versa
what is transpiration?
process by which water evaporates through openings on the underside of the leaves known as stomata. equiv to humans sweating, cools the vine
what is translocation?
metabolic process in which materials eg, sugar, are moved from one part of the plant to another
how much water do vines need annually?
20 - 30 inches
the 3 particle sizes
clay (smallest)
silt (intermediate)
sand
gravel (largest)
which of the 3 particle sizes has the lowest water retention capability
gravel
the higher the latitude, the ____ the growing season
shorter
Mediterranean climates have (dry/wet) winters and (dry/wet) summers
wet winters, dry summers
how are viral diseases spread?
by propagating infected vine cuttings
What is Pierce’s disease and what does it result in?
bacterial disease - results in premature leaf fall
in what conditions are fungal diseases considerable?
warm, humid
the two most damaging fungal disease
powdery mildew aka oidium
downy mildew aka peronospora
peronospora aka
downy mildew
what is a nematode?
microscopic roundworm that feeds on the roots
why do you not want the vines to be too productive?
the vines can gather only so many nutrients - too many grapes and it will spreads itself thin
the two main strategies for pruning
spur pruning
cane pruning
what is cane pruning?
all but one or two canes are removed per vine. the remaining canes are than attached to a trellis and trimmed so that each cane has 6-10 buds
what is spur pruning?
vine is training to develop one or more cordons - each will suppoort everal canes. annual pruning cuts back the spurs, leaving behind spurs
what is a spur?
small portion of a cane containing several buds
what is the guyot system?
one or two canes or cordons are trained along a wire
Geneva Double Curtain, Lyre, Scott Henry are all examples of..
divided canopies
synonyms for bush vines
head-trained vines
gobelet-style vines
what is a bush vine?
vine with thick trunk, typically free standing and spur pruned
gobelet-style vines are typically ___ pruned
spur
How is sugar concentration measured in US?
degrees Brix
How do you estimate the potential ethanol level in a finished dry wine?
55% of the Brix value
What system of sugar measurement does France use?
Baume
grape juice with 12 degree Baume will have a max ____% alcohol
12
organic viticulture is grape growing without the use of ____ fertilizers or ______
manufactured / pesticides
What is Integrated Pest Management?
system in which only harmful pests are targeted - sparing insects that may be beneficial
