The Growing Environment Flashcards
Below what temperature does a vine go dormant?
10 ° C
Define climate.
The annual weather pattern of an area averaged over several years.
Define “Cool Climate” and give examples.
Regions with an avg temp during the growing season of below 16˚ C, in which early ripening varieties (Chard, PN) will just ripen
Ex.: Champagne, the Mosel, Southern England, Anderson Valley, Tasmania, parts of Carneros.
Define “Moderate Climate” and give examples.
- Regions with an avg. temp. during the growing season btwn 16.5 - 18.5˚ C.
- Suited to the production of med bodied wines from intermediate ripening varieties such as C. Sauvignon, Merlot, and Sangiovese.
- Ex.: Bordeaux, Northern Rhone, Rioja, most of Piemonte and Tuscany. Also Coonawarra, Marlborough, and the more moderate parts of Napa and Sonoma.
Define “Warm Climate” and give examples.
Regions with an average mean temperature during the growing season between 18.5 - 21˚ C. These are suited to heat loving varieties such as Ruby Cabernet, Mourvedre, and Grenache. Often, fortified wines such as Port and Liqueur Muscat are produced Examples include the Southern Rhone, Jerez, McLaren Vale, Paarl, and the Douro.
What is “Continentality”?
Continentality is the difference between the average mean temperature of the hottest month and the coldest month. Where the difference is large, climates are continental. When they are small, climates are maritime.
Define “Maritime Climate” and give examples.
Characterized by low annual range of temperatures combined with relatively high levels of rainfall. The ripening period is reasonably long with moderate temperatures. These are usually found near large bodies of water. Rainfall during the growing season tends to be higher than either Mediterranean or Continental climates, and this brings extra cloud cover: this coupled with moderate temperatures make maritime climates ideal for the production of medium bodied wines with moderate alcohol levels. Examples include, Muscadet, Bordeaux, Rias Baixas, Vinho Verde, Southern England, and the eastern coast of New Zealand.
Define “Mediterranean Climate” and give examples.
Characterized by low annual range of temperatures but with dry summers and wet winters. The dry, sunny growing season is suitable for a wide range of wine styles – but in particular, full bodied and richly textured reds with ripe tannins. Examples include those around the mediterranean, but also most of Chile, most of South Eastern Australia, parts of the United States’ West Coast, and the Cape in South Africa.
Define “Continental Climate” and give examples.
Characterized by wide annual range of temperatures with hot summers and cold winters. Generally found inland away from the moderating effects of the sea. In regions far from the equator this results in warm but short summers. The combo of long day length and continentality makes viticulture viable in the northern regions of Germany, Champagne, and British Columbia. Requires the use of early-ripening varieties. Drier than Maritime = less risk of rot at harvest, so late harvesting is less of a risk. Examples include Alsace, Wachau, Burgundy, Mendoza, Central Spain.
Define “Tropical Climate” and give examples.
Minimal annual temperature variation so seasons tend to be defined not by temperature but by other factors (i.e. rainfall). Because the vine needs clear temperature signals for its dormant period and growth cycles, tropical and sub-trobical climates are considered unsuitable for high quality viticulture – even in locations where temperature is moderated by altitude or proximity to cool oceans. Examples include Brazil and India but the lack of winters can mean a vine crops more than once a year and with no dormant period with which to rest – Because of this, vines in these climates have a shorter lifespan.
Explain the role of Glucose to the vine.
Glucose is the building block of the vine: Sun, Water, and CO2 are photosynthesized to make it. Glucose molecules are combined to make larger carbohydrates, including cellulose which helps build the roots, trunk, shoots, leaves, and fruit. It is also the basic building block for the creation of tannin, acids, and flavor molecules within the grape.
At what temperature does vine growth peak?
Typically between 22 - 25˚C. Above this, the vines metabolic needs increase faster than its ability to photosynthesize sugars so growth slows.
Explain the role of Glucose to the vine.
Glucose is the building block of the vine: Sun, Water, and CO2 are photosynthesized to make it. Glucose molecules are combined to make larger carbohydrates, including cellulose which helps build the roots, trunk, shoots, leaves, and fruit. It is also the basic building block for the creation of tannin, acids, and flavor molecules within the grape.
At what temperature does vine growth peak?
Typically between 22 - 25˚C. Above this, the vines metabolic needs increase faster than its ability to photosynthesize sugars so growth slows.
Why are western facing vineyards disadvantageous?
Vineyards facing west, towards the setting sun, face a triple disadvantage: They do not catch the sun as it rises in the morning as east facing vineyards do, their sunlight will be scattered by dust that has been lifted by warming air during the day; and they tend to face damper cooler prevailing weather conditions.
What are some advantages to a sloped vineyard?
— Sunlight reduces in intensity as he angle at which it hits the ground reduces from 90˚ to 0˚ – Partly due to the light beams having to travel through a greater thickness of atmosphere to get to the ground (and thus more energy being absorbed), but mostly due to the fact that the available sunlight is dispersed over a greater area of land. — Soils on slopes tend to be poorer, coarsely textured, and better drained, moderating vine vigor. — If the vineyard is on a slope, the cold and relatively dense air moves downhill. The sinking cold air displaces warmer, less dense air to higher levels producing warm thermal layers on the slope. Above the warm layers air temperature again drops, which is why, for example, the best vineyards of the Cote d’Or run along the middle band of the slope. This air movement on slopes is especially valued in cooler climates as the air movement deters frost and offers slightly improved ripening potential.
What are some disadvantages to a sloped vineyard?
— Increased risk of Erosion, although other factors such as rain intensity as well as soil texture and structure play a major part. — Higher costs incurred to harvest than flat ones. Must be worked by hand.
What are the advantages of “Isolated Hills” and give examples?
Examples: The hill of Corton, Somló, and Montagne de Reims. These are ideal vineyard sites because there are no big currents of colder air flowing down from the main hills.
What are some advantages and disadvantages to vineyards near bodies of water?
Advantages: – Reflects sun’s rays – Provides water for irrigation – Reduces risk of ground frost – Can provide morning mists to encourage the development of ‘Noble Rot,’ which may be desirable. Disadvantages: – Increases humidity of a sight, which increases the risk of fungal disease, in particular downy mildew.
What are some advantages and disadvantages to vineyards near bodies of forests?
Advantages: – Act as windbreaks – Store heat in cold weather – Increase humidity Disadvantages: – Harbor large flocks of birds which feed on and damage grapes.
Name some effects of a thick vigourous canopy.
– Reduces flower initiation and berry set due to shading. – Results in higher levels of acid retention due to cooling. – Reduces sugar accumulation due to an increase in humidity and shade from the vigourous canopy. – Encourages competition between vigorously growing shoot tips and berries for sugar, which reduces berries’ ability to fully ripen.
How does temperature affect 1) the yield of a vineyard 2) The quality of a winegrape crop?
1) – Vigor of the vines – # and size of flower cluster – success of the setting of these into berries. 2) – level of yield obtained – accumulation of sugars and the reduction of acidity in the berry. – the development of wine aromas and their precursors.
At what temperature will vines be affected by freeze injury?
Begins at -15˚C, is serious at -20˚C, and can be fatal at -25˚C – Unless the vine is insulated by snow or earth pushed up around it. A site will usually be considered unsuitable for viticulture if its temperature falls below -20˚C more than once every 20 years or if the mean temperature for the coldest month is less than -1˚C.
How is the Amerine and Winkler heat summation (1944) calculated?
Mean temperature of the month - 10˚C (Min temp for vine growth) x number of days in the month –> Monthly sums are totaled for the 7 months of the growing season. Category 1 (2200) – Bulk wines, table and drying grapes.
Above what temperature does vine growth slow?
30˚C
What are some effects of sunlight on vine growth?
– Direct effect on the rate of photosynthesis – Direct effect on bud viability, initiation of vine flowers, berry ripening, and cane maturation. – Indirect effect due to heat accumulation.
How many hours of sunshine is required for Vitis vinifera to ripen ripe fruit?
- Additionally, the amount of available sunshine will decrease by up to 10% if the vineyard is located near a large town or city, due to pollution effects.
How does altitude influence temperature?
The mean annual temperature decreases by .6˚C with every 100 meter rise above sea level.
What factors influence soil fertility?
– Soil texture – Soil structure – Organic matter content – Mineral content – Availability of air and water – Level of acidity/alkalinity
What is soil texture?
The size of the particles that make up soil, and their proportions relative to one another. They are graded according to their diameter in mm: 0 < Clay < 0.002 < Silt < 0.02 < Fine Sand < .2 < Sand < 2 < Gravel < 2+ Most soils contain a mixture or particle sizes. Soil texture can be assessed by touch.
What are some disadvantages to clay soils?
Clay soils hold more minerals, as their particles are negatively charged, but they have several disadvantages. — They take longer to heat in the spring and tend to be colder all year round because they hold more water. — They swell when they absorb water, and shrink when they dry. This can cause severe cracking through which water is quickly lost. This cracking also can damage root systems. — As clay becomes wet, it becomes very sticky. — When wet clay soils are worked, their structure deteriorates.
What is loam?
The texture of soil with ideal fertility. It is a mixture of clay, silt, and sand. It combines the nutrient holding capacities of clay, with the good drainage capabilities of sand.
What is limestone? Where is it found?
Sedimentary rock formed from the deposition of shells and skeletons of marine animals. It consists largely of calcium carbonate, is usually alkaline and free draining. Many classic wine regions have limestone soils including central and eastern Loire, Piemonte, most of Burgundy, northern Spain, and the Limestone Coast in South Australia.
What is chalk? Where is it found?
Chalk is formed in the same way as limestone but has a lower density and so is even more free draining. Very pure chalk soils are found in Champagne and Jerez.
What are 3 sedimentary rocks important to vine growing other than limestone and chalk?
Dolomite: Similar to limestone but with high levels of magnesium. Sandstone: Composed of compressed sand (Quartz) particles. Shale: Sedimentary rock that was originally composed of clay and is quite soft.
What is slate?
Shale that has been altered through high pressures and temperatures (Metamorphosis). Harder and less porous than shale. Found in the Mosel, for starters.
What is granite?
An igneous rock. Extremely hard and dense but still free draining. Common in Baden and the Northern Rhone.
What is soil structure?
The way in which soil particles form lumps or crumbs. It affects the availability of water and air to plants and the ability of fine feeding roots to penetrate the soil and exploit the essential plant nutrient supply. Soil structure is influenced by: Organic Matter, earthworms and other organisms, wetting and drying, freezing and thawing, presence of plant roots, cultivation and other soil management practices, texture, drainage, compaction.
How is good soil structure measured? What are the pitfalls of poor soil structure?
Where the particles form stable clumps of 1-5mm in diameter. For this to happen there has to be 3-10% organic matter. Poor soil structure can lead to: – Capping/Crusting: When soil surface hardens. – Puddling: where rainwater sits on surface of crust and causes extensive erosion. – Sieving: where clay particles are carried along with water draining through the soil and deposited lower down, sometimes forming a layer that prevents the aeration and drainage of the soil.
What is humus? Benefits?
Organic matter in soil broken down by soil organisms, composed of plant and animal remains and animal excreta that has decomposed. It is composed of – Sugars, starches, cellulose, and nitrogenous compounds. – Lignin and mineral matter. Benefits: – maintenance of soil structure, as it helps bind particles. – retention of available nutrients, as it helps bind particles – a high water holding capacity makes more water available to plants. – low plasticity and cohesion, which makes soil management easier. – there is a gradual release of available nutrients as the humus is slowly mineralized. – darkening of color, which increases soils ability to absorb heat.
What are soil layers?
As soil is formed, the different structural and textural types will form layers, which can be investigated by digging a soil profile. A soil profile reveals the depth of these layers, and if there are any drainage or root barriers in the soil which will prevent its exploration by plant roots.
How many mm of water are required to satisfy a vines needs?
- Even more in hot conditions.
Describe some ways in which soil aeration is helpful.
– Provides oxygen to aerobic organisms and surprises the growth of harmful anaerobic ones. – Provides roots with essential oxygen for respiration and growth. – Removes carbon dioxide and other waste gases formed by the breakdown of organic matter and by plant roots.
Explain the role of nitrogen to the vine.
– Second only to water in importance to plant growth. – A major constituent of plant cell proteins, nucleic acids, chlorophyll, and hormones. – Encourages vigorous shoot growth which can shade fruit and inhibit ripening. Fertile soils have large amounts of available nitrogen.
Explain the role of phosphorus to the vine.
– Key element in energy fixation. – Encourages berry ripening and root growth.
Explain the role of potassium to the vine.
– Regulates the flow of water and sugar in the plant. – Encourages berry ripening.
Explain the role of calcium to the vine.
– Regulates cell acidity. – Important component of cell walls.
Explain the role of sulfur to the vine.
– Essential constituent of some amino acids and enzymes.
Explain the role of magnesium to the vine.
– Essential component of chlorophyll. – Regulates internal acidity and sugar metabolism. – Encourages ripening.
Name some trace elements that are important to the vine in small amounts.
Boron, Manganese, Copper, Iron, Molybdenum, Zinc, Cobalt, Chlorine, Silicon.