Wine lect5
- 1. 9/10/2012 Introduction to Vines and Wines Hort/VE 113 Fall 2012 Session 5 -Grape Growing: climate and environment Climate terminology • Climate: the average course or condition of the weather at a place usually over a period of years as exhibited by temperature, wind velocity, and precipitation. • Mesoclimate: the climate of a vineyard site; up to a region; influenced by prevailing winds, proximity to water. • Microclimate: the climate of the grapevine canopy. Meso Climates • Meso – sites within a region – air drainage, soil, water table, slope, aspect, aspect orientation – Small end: an extensive vineyard – Large end: a region– Note: there are many Meso climates possible in a given region 1
- 2. 9/10/2012 Micro climates • Micro – From the scale of inches to the scale of a few hundred yards – From the scale of a leaf to the scale of a vineyard. 2
- 3. 9/10/2012 Important climatic characteristics • Sunshine • Heat accumulation (growing degree days) • Length of growing season (number of y frost-free days) • Cold dormant “chilling” period • Absolute minimum temperature • Humidity • Rainfall during growing season American Viticultural Areas “AVA’s” • Concept of AVA’s— – Federally recognized growing regions – American Viticultural Areas – Designed to give you a geographic and climatological pedigree for the wine coming from that AVA – Also called “Appellations” The AVAs of WA • Puget Sound • Columbia Gorge • Red Mountain • Wahluke Slope • Walla Walla Valley • Snipes Mountain • Yakima Valley • Lake Chelan • Horse Heaven Hills • Columbia Valley • Rattlesnake Hills • Pending: Naches Heights; Ancient Lakes 3
- 4. 9/10/2012 AVA’s were established to help people try to guess the properties of wines without tasting them. • e.g., If you bought a nice Pinot Noir from one vineyard in the Puget Sound, you might be able to assume some of h b bl f the characteristics of another Pinot from another winery in the same AVA. 4
- 5. 9/10/2012 Sunlight • Desirable regardless of which varieties are grown or the end use • Required for photosynthesis (production of carbohydrates) f y ) • Heats fruit and accelerates ripening • Stimulates development of fruitful buds • Helps dry foliage and fruit – reduces disease Heat Accumulation • Growing degree days (GDDs): used to predict development of crop and determine where grapes will grow • GDDs (base 50˚F) = average daily temperature – 50 for a given 24 hour period: • Average the min and max temps and subtract 50 degrees • High of 60 low of 50: • 60+50 divided by 2 = 55 • 55-50 = 5 GDD • Counted from April 1 to October 31st. www.weather.wsu.edu Average air temp (F) 2 Sept 2008 5
- 6. 9/10/2012 Prosser, WA GDDs Base 50 GDD Calculation Wine grapes need high GDDs to accumulate sugar in fruit • >2500(F˚) preferred for red varieties: –C b Cabernet Sauvignon, M l t M lb tS i Merlot, Malbec • >1900 preferred for white varieties – Pinot Noir, Pinot Gris, Riesling, Gewurztraminer, Muscat, Chardonnay 6
- 7. 9/10/2012 Classification by Maturity Growing degree days (GDD, 1 April - 31 October, base temperature 10°C) required to reach acceptable maturity GDD Group Red varieties White varieties (C.) 1 1050 Madeleine Angevine Chasselas, Muller- 2 1100 Blue Portuguese Thurgau, Pinot gris Gewurztraminer, 3 1150 Pinot noir, M Pi i Meunier, G i Gamay Sylvarer, Ch d S l Chardonnay, Sauvignon blanc Semillon, Muscadelle, 4 1200 Malbec, Zinfandel, Pinotage Riesling Merlot, Cabernet franc, Syrah, 5 1250 Chenin blanc Cinsaut, Barbera, Sangiovese 6 1300 Cabernet Sauvignon Colombard, Palomino Muscat of Alexandria, 7 1350 Aramon, Carignan, Grenache Ugni blanc 8 1400 Tarrango, Terret noir Clairette, Grenache blanc Length of growing season • Number of continuous days without frost • Frost can freeze buds in the spring, eliminating crop • Frost can cause leaves to drop early, limiting carbohydrate reserves that are stored over winter Chilling period • Required for buds to “break” in spring – Accumulated degrees below a certain threshold • Not usually an issue in the temperate climates • Makes tropical viticulture difficult 7
- 8. 9/10/2012 Absolute minimum temperature • Cold temperatures can kill buds, canes, trunks, even entire vines! • High variation in cold hardiness among h di species and cultivars • Makes temperature moderation by water (oceans, large lakes) important • -10˚F damages most V. vinifera varieties Continentality = effects of bodies of water, slope, elevation on wind generation The wind can act to protect grapes from freezing, overheating and can remove excess moisture 8
- 9. 9/10/2012 Humidity and rainfall • Encourage fungal diseases such as powdery mildew and downy mildew • Rainfall sometimes provides more water than desirable • Dry climate with irrigation reduces disease and allows the grower to stress the vine at the appropriate time Soils • Well drained generally best – Mixtures of sand, gravel, organic matter • Drainage can be improved with drainage tile • Many wines benefit from the mineral content of the soil– sometimes chalky • Rootstocks are selected for soil characteristics (texture, pH) Soil types Alluvial - A combination of clay, silt, sand and gravel that forms over time from mineral deposits left by running water. Granite - A hard and granular rock with a high content of crystals, particularly quartz. Jory - A volcanic soil composed mostly of basalt, which is in turn a hard and dense soil that often has a glassy appearance. Limestone or Chalk - A soft soil made primarily from fossilized seashells. seashells Loam - A crumbly mixture of clay, sand and silt. Marl - A crumbly mixture of different clays as well as calcium and magnesium carbonates with fossilized shells mixed in as well. Sandstone - A combination of silica and sand compacted together by pressure and time. Tufa - A mix of silica, calcium carbonate and sometimes volcanic ash that has been deposited over time by streams, lakes and other water sources. 9
- 10. 9/10/2012 “Terroir” A French term (much discussed) for the total natural environment of any viticultural site Major components have been described: Soil Macro-,meso-, and microclimates “Terroir” Determinants of terroir include: • Climate-temperature and rainfall • Sunlight energy-received per unit of g gy p land area • Topography-altitude, slope, and aspect • Geology – more on this later • Hydrology –soil water relations Fine wines • All involve matching the grape variety to the local “terroir” • Viticulturists have learned how to manage the vines to achieve the best results for that particular location • Certain climate years yield outstanding “vintages” 10
- 11. 9/10/2012 Introduction to Vines and Wines Hort/VE 113 Fall 2012 Sessions 6 & 7-Grape Growing pruning and training Lesson Objectives: Learn the importance of pruning in vine and crop management Understand how pruning affects crop l d and vegetative growth load d t ti th Understand how pruning levels affect fruit quality Concepts of Pruning What is pruning? What is the difference between pruning and training? Pruning is the removal of unwanted wood or parts of the vine…and f h i d Training is the establishment of the permanent vine structure or form. 11
- 12. 9/10/2012 Why prune? 1. Establish and maintain vine structure and cropping 2. 2 Distribute crop load 3. Control and adjust crop load 4. Maintain or control vegetative growth The principal objective of pruning is to maintain a balance between fruiting (crop load) and vegetative growth (canopy) 12