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GRAPE RESEARCH NEWS WINE - Viticulture and Enology

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GRAPE RESEARCH NEWS WINE - Viticulture and Enology Powered By Docstoc
					Washington State University
               WINE                                                                                                           Calendar

                                                                                           January 31, 2003 Pre-registration deadline for Viticulture Certificate




                                 &
                                                                                               Program.   http://winegrapes.wsu.edu (follow the links)

                                                                                           January 28-30, 2003. Unified Wine & Grape Symposium, Sacramento CA.
                                                                                                http://www.unifiedsymposium.org/

                                                                                           February 3-5, 2003. Washington Association of Wine Grape Growers
                                                                                               Annual Meeting. http://www.wawgg.org/

                                                                                           June 2003. Annual Meeting of the American Society of Enology &
                                                                                               Viticulture, Reno NV. http://www.asev.org/




GRAPE RESEARCH NEWS
            Volume 13                   2002                                                                                                              Editor: Sara Spayd

    Viticulture & Enology Education Consortium News ........................ 1
    Viticulture Certificate Program ......................................................... 1               information via e-mail and/or snail mail in the very near future.
    WSU Pullman Enology .................................................................. 2                  Total cost for the 131 hours of instruction is $2995. Price of indi-
    Grape & Wine "Newbie" Corner .................................................... 2                       vidual units varies depending on length. The program is lim-
    Terrior — What It Is and How To Use It .......................................... 2                       ited to an enrollment of 30 participants. Individuals registering
    Tales of the Purple Grape ................................................................ 4
                                                                                                              for the entire program will be given preference over those
    Student Awards .............................................................................. 6
    Enology/Viticulture Education ......................................................... 6                 registering for less than the full program. I would like to take
    New Viticulture Position ................................................................. 7              this opportunity to rationalize some of the incongruences that
    Riesling Production in WA State ...................................................... 7                  developed during the development of this program.
    Guidelines for Sampling Nematodes from Vineyards in the PNW .... 9
    2002 Growing Season in Perspective ........................................... 10                              First, we fully recognize that evenings and weekends would
                                                                                                              provide the best schedule for many of our potential students.
                                                                                                              However, this will not be possible for all of the units in the
Viticulture & Enology Education Consortium News                                                               program. Depending on the course, classes will be offered ei-
     Dr. Ray Folwell, WSU Professor of Agricultural Economics, is                                             ther Thursday evenings, Friday afternoons, or Saturday morn-
serving as Interim Coordinator of the Washington Viticulture                                                  ings with one all-day Saturday class. We recognize that it may
and Enology Consortium. Dr. Folwell received his B.S. in Agri-                                                be difficult for many employers to release employees for day-
culture and his M.S. in Agricultural Economics from the Univer-                                               time classes. Wherever, possible in the schedule we have tried
sity of Illinois, Champaign-Urbana and completed his Ph.D. in                                                 to avoid the Friday afternoon sessions. I hope the industry is
Agricultural Economics at the University of Missouri, Columbia.                                               willing to be flexible and creative in accommodating their em-
He has been with Washington State University since 1968. Dr.                                                  ployees’ wish or the employers’ wish for their employees to
Folwell has received considerable recognition for his teaching,                                               obtain further education. This is a partnership. We created this
research and service. He received teaching awards from the                                                    program because the industry asked for new programs.
American Agricultural Economics Association, WSU College of
                                                                                                                   Second, some of the classes of a given unit are taught dur-
Agriculture and Home Economics, National Association of Col-
                                                                                                              ing very active periods of the growing season, including Sep-
leges and Teachers of Agriculture, Western Region-USDA, and
                                                                                                              tember. Again, we recognize the inherent problems of release
others. For his research and service to Washington agricultural
                                                                                                              time during more active periods of the growing season. One of
industries, Dr. Folwell received the Walter Clore Award from
                                                                                                              the running themes I have heard coming from the Washing-
the Washington State Grape Society and the Friend of the In-
                                                                                                              ton Industry is a desire for courses that provide “hands-on”
dustry Award from the Washington/Oregon Asparagus Asso-
                                                                                                              experiences to be part of any and all extension programming.
ciation. He was a recipient of a NATO Guest Fellowship to Italy
                                                                                                              Courses in this program are timed for the optimum teaching
and served as a Visiting Professor at the University of Bologne
                                                                                                              experiences in a given expertise. Examples of this are: Soils
from 1987 to 2000.
                                                                                                              and nutrition classes are scheduled for the spring and in con-
                    Viticulture Certificate Program
                                            Program                                                           junction with the irrigation classes. How do you teach petiole
Sara Spayd, Ext Food Scientist/Food Scientist, FSHN, WSU Prosser                                              and soil sampling when there are either no leaf tissues to col-
      On February 7, 2003, WSU Cooperative Extension in con-                                                  lect or the soils are too frozen to soil sample? Insect and disease
junction with the Washington Wine Education Consortium will                                                   related classes are scheduled for August and September be-
launch a certificate program in viticulture. The program con-                                                 cause that is when these organisms can best be found and
sists of 10 units of nonacademic credit courses of varying length.                                            discussed. Again, this is not convenient for employers, but pro-
Instruction is spread over a 20-month period. You will receive                                                vides the best educational opportunity.


                                                                                                          1
    Third, I recognize that there is a great desire to offer this                     Grape & Wine “Newbie” Corner
program statewide using the Washington Higher Education Tele-
                                                                         The term “Newbie” comes from the old Southern phrase “ I be new” in
communications System (WHETS). We strongly considered this               this case to grapes/wine or to a program. From S. Spayd’s book of
possibility. We ran into a number of stumbling blocks.                   Corrupt Southernese
      I bring these issues up because I want you, the Washington              Alan Busacca is professor of soil science in the Department
Industry, to know that we are trying very hard to bring you the          of Crop and Soil Sciences and affiliate professor of geology in
programs you need and want. We thank you for all of your                 the Department of Geology at WSU Pullman. His teaching
help, input, and funding for the development of this program.            focus is world agricultural systems and Pedology, which is the
Any “profits” that are generated by this program will be plowed          study of the origin, nature, and properties of soils. He also is
back into this program and the development of the enology                assisting Kathleen Willemsen in teaching the new WSU
certificate program. Once the viticulture certificate program is         Viticulture course. In addition to his regular teaching duties,
up and running, we will be developing a parallel certificate             Alan offers frequent talks, short courses, and field trips through-
program in enology. We will face many of the same concerns               out the region for growers, foresters, geologists, soil scientists
and issues as those experienced developing the viticulture cer-          and the general public. Alan’s research interests include the
tificate.                                                                unique soils, landscapes, and recent geologic history of the
                                                                         Pacific Northwest, soils and viticulture, soil erosion by wind and
     Thank you again. We know that your comments and criti-              water, soil and water conservation, and soil-landscape model-
cisms come from your interest in these programs. Indifference            ing in wilderness areas.
is the poison!
                                                                              Dara (pronounced Dar-uh[the Dar rhymes with Tar] ) Russell
                 WSU - Pullman Enology
                       Pullman                                           and Maria Mireles joined the WSU-Prosser Enology team dur-
C. Edwards, Professor, Food Science & Human Nutrition, WSU Pullman       ing the past 6 months as Research Technologist III and Research
     As many of you are aware, I was on a sabbatical leave to            Technologist I, respectively. Dara is handling HPLC and GC-MS
Chr Hansen (Horsholm, Denmark), the manufacturers of                     duties. Maria is managing the wine sensory panel, grape and
Viniflora and other products. It has been an incredible year             wine analysis, and wine making duties.
with a lot of travels through the wine regions of Germany
and France along with family trips through the Nordic coun-
tries. I have been involved in a number of research projects,
                                                                                  Terroir - What it is and How to Use it
including one in which I guided a student (equivalent to a MS            Larry Meinert, Department of Geology, WSU Pullman
degree) from the agricultural university in Copenhagen.                       It seems like everywhere you look these days - wine labels,
     From a research point of view, the laboratory in Pullman            newspapers, magazines and even restaurant menus (!), people
continues to work in two areas; (a) impact of various micronu-           are talking about terroir. In fact, at the 2002 Washington Asso-
trients on yeast physiology and subsequent wine quality and              ciation of Wine Grape Growers annual meeting, the keynote
(b) malolactic fermentation. Two students are involved in the            speech by Paul Gregutt, Contributing Editor - Wine Enthusiast
micronutrient research which focuses on metabolic interac-               Magazine, concluded that terroir is going to become the single
tions between must nitrogen and vitamins, primarily biotin               most important criterion for distinguishing among high end
and pantothenic acid. While one student is examining the                 wines. But the word terroir is mysterious to many people, with
impact of these variables on yeast performance during fer-               confusion about what it is, how it is documented, and even
mentation (including H2S evolution), the other is performing             how to pronounce it (tehr-wahr).
a survey to determine concentrations of these vitamins in                    My colleague, Alan Busacca (Crop and Soil Sciences - WSU),
grape cultivars grown in Washington. Preliminary results in-             and I have given numerous talks and written a series of papers
dicate that grapes grown in our state are very low in some               on terroir in an attempt to demystify it and provide a scientific
vitamins, particularly pantothenic acid. This has strong im-             basis for its documentation and interpretation. Simply put,
plications regarding H2S formation.                                      terroir involves the complex interplay of climate, soil, geology,
     One student is involved in malolactic fermentation, study-          and culture that influences the character and quality of wine.
ing how yeast are able to frequently inhibit malolactic bacte-           Although the term originated in France, terroir increasingly is
ria and subsequent MLF. This research is being conducted                 being used in other parts of the world to explore differences at
jointly with Chr Hansen. Though one theory has been that                 the scale of appellations to individual vineyards to within-vine-
yeast produce enough SO2 to kill bacteria, very little free SO2          yard domains (e.g., Wilson, 1998, 2001; Haynes, 1999, 2000).
has been detected using some new equipment (a capillary                       One common illustration of the importance of terroir is the
electrophoresis unit) at Chr Hansen. Protocols have been                 occurrence of adjacent or nearby vineyards that produce strik-
worked out to measure free SO2 using this equipment).                    ingly different wines even though many of the measurable
     Finally, it is with much excitement that we announce our            aspects of climate, viticulture, and winemaking technique are
laboratory has been successful in obtaining a research grant             very similar. It is also common, although usually incorrect, to
from the American Vineyard Foundation. The grant ($25,000)               point to a single factor as the explanation: “It’s the soil.” “It’s
will support a student this coming year working on Lactoba-              the water.” “It’s the limestone.” etc. Terroir is the integration
cillus infections. We are most excited about this project and            of individual factors that contribute to wine quality and to make
sincerely thank AVF for the support.                                     matters even more complicated there is the variable of time.


                                                                     2
What may be good terroir in one year may be less so in an-                basis of slope, grain size, and other characteristics that affect
other. For example, in years that are relatively warm and dry,            soil use by people. For example the Prosser silt loam, 0-2 per-
vineyard “X” with a particular slope, elevation, sun angle, and           cent slope, is one subdivision of the Prosser soil series. Since
soil type may produce better wine than vineyard “Y”, whereas              slope varies continuously throughout most vineyard areas, it is
the reverse may be true in years that are cooler and wetter.              useful to display this information using topographic maps with
                                                                          contour lines of equal elevation. Topographic maps are avail-
    With all these variables, how does one make sense of terroir?         able for most of the United States at a variety of scales (http://
Luckily, the individual factors and measurements are mostly               mcmcweb.er.usgs.gov/topomaps/).
common sense and much of the information has already been
compiled, if you know where to look and what to look for. As                   Collectively, geologic, topographic, and soil survey maps
an example I will outline the steps that we have used in docu-            provide essential data for any characterization of terroir. This
menting the terroir of two of Washington’s newer appellations,            information is widely available at the sources listed above and
Red Mountain (Meinert and Busacca, 2002) and Walla Walla                  represents the starting point for a terroir study of any particu-
(Meinert and Busacca, 2000).                                              lar region, appellation, or individual vineyard. For example,
                                                                          the Ciel du Cheval vineyard in the Red Mountain AVA has a
     The geologic history of an area is probably the most fun-            relatively low slope with homogeneous air drainage and
damental aspect of terroir but may also be the most difficult to          mesoclimate. There are three different soil types exposed in
understand for those without technical training. The geologic             the vineyard that cut across the N-S rows of vines. The Ciel du
forces that produce mountain ranges like the Cascades, volca-             Cheval vineyard has been owned and managed by a single
noes like Mt. St. Helens, rivers like the Columbia, and glacial           person, Jim Holmes, for nine years and thus has a consistency
epochs that reshape the landscape are fundamental to the                  of management style that might allow for examination of pos-
ultimate siting of individual vineyards. Luckily there are several        sible viticultural and enological variations as a reflection of soil
guides to regional geology that are written to help people un-            type. Initial results of grape analyses suggest that there are
derstand the geological history and setting of a region. Per-             differences that might correlate with soil types and an ongo-
haps the most widely available is the Roadside Geology series             ing study of wine sensory analysis over a three year period has
published by the Mountain Press Publishing Company of                     been designed to test whether different soil types can be cor-
Missoula, MT and widely available in regional bookstores or on            related with statistically significant wine flavor profiles. Such
the Internet (http://www.mountain-press.com/otherpages/                   sensory differences have been correlated previously with a va-
GEOLOGY/bookpage/RGofWA.htm). At a more detailed level                    riety of terroir variables (e.g., Douglas et al., 2001).
there are geologic maps covering most of the United States at
a variety of scales. For the State of Washington a good starting               Climate is one of the more important components of terroir.
place is the Department of Natural Resources (DNR) web site               In some ways it is the most difficult to evaluate because it varies
(http://www.wa.gov/dnr/htdocs/ger/geomaps.htm) which lists                in both space and time. There are many weather variables
both DNR maps and area map resources such as local univer-                and these can be measured at three different scales.
sities. These maps describe and plot the location of rock types           Macroclimate is on a continental to regional scale and controls
within a given geographical region.                                       the length of the growing season and other long-term trends
                                                                          and extremes. Mesoclimate is on a regional to vineyard scale
      For most Washington vineyards the bedrock is a hard black           and is affected by topography, elevation, slope, aspect, and
rock called basalt that formed 10 to 20 million years ago as              proximity to bodies of water or other moderating influences.
immense lava flows (somewhat similar to those presently spout-            Microclimate ranges from the scale of a vineyard down to indi-
ing from volcanoes in Hawaii). However, the basalt rock usu-              vidual vines, grape clusters, and even smaller domains if mea-
ally is overlain by sands and other sediments deposited by huge           surement permits. Macroclimate can vary on a geologic time
glacial floods that occurred about the same time as the first             scale (millions of years) but both mesoclimate and microcli-
human settlement of North America, approximately 15-20,000                mate can vary seasonally, daily, or even hourly. Both mesoclimate
years ago. These rocks and floods are described in more detail            and especially microclimate can be affected by human activi-
in Meinert and Busacca (2000, 2002).                                      ties such as urban development, wind machines, irrigation,
     As interesting as the bedrock is to a geologist, few grape-          and canopy management.
vines can grow in solid rock and thus the soils developed on                   Although many climatic variables can be measured, four
these materials are of immediate interest to all vineyardists.            of the more important are temperature, humidity, wind, and
Soil development is an ongoing process that is the culmination            sunlight (solar radiation). These and others are collected sys-
of hundreds to millions of years of weathering. Just like maps            tematically by a variety of meteorological services but in the
of bedrock geology are available for most of the United States,           state of Washington we are fortunate to have the WSU Public
maps of soil types are available from the United States Depart-           Agricultural Weather System (PAWS) that automatically and con-
ment of Agriculture Soil Conservation Service (http://                    tinuously collects climatic data (http://frost.prosser.wsu.edu/).
www.wa.nrcs.usda.gov/Tech_Resource/Soils/). These are usu-                For the Red Mountain and Walla Walla terroir studies, we uti-
ally organized by county and most include detailed aerial pho-            lized PAWS data to document averages for the appellations as
tographs with overlays of the main soil series. Each soil series is       well as variations among vineyards. For example, most of the
named after a local town or geographic feature and has a                  Red Mountain AVA has on average 200 more growing-degree
characteristic soil profile. Soil series can be subdivided on the         days than Yakima Valley, and Walla Walla has more than twice


                                                                      3
the precipitation of Red Mountain. Regional and world-wide               ing the best wine in a given setting. Much remains to be
comparisons are also possible, e.g. the excellent analyses of            done.
Gladstones (1992, 2001).
                                                                         References Cited:
     Similar regional comparisons are possible using the other           Douglas, D., M. A. Cliff, and A.G. Reynolds. 2001. Canadian terroir: char-
types of terroir data discussed previously. For example, more              acterization of Riesling wines from the Niagara Peninsula. Food Re-
than 90% of Washington vineyards are located in areas af-                  search International 34:559-563.
fected by glacial outburst floods thousands of years ago. In
                                                                         Gladstones, J., 1992, Viticulture and environment: Winetitles, Underdale,
the Red Mountain area, these flood sediments were mostly                   Australia, 310 p.
deposited from the swirling back-eddies behind Red Moun-
tain and include numerous lenses of relatively coarse gravel.            Gladstones, J., 2001, Climatic indicators guide site selection: Practical
In the Walla Walla area, the flood sediments are generally                 Winery & Vineyard: v. 23, p. 9-18.
finer grained due to deposition from ponded floodwaters, al-             Haynes, S.J., 1999, Geology and Wine 1. Concept of terroir and the role of
though there are some zones of coarse gravels in modern                    geology: Geoscience Canada, v. 26, p. 190-194.
river channels. Many other wine-producing areas of the world             Haynes, S.J., 2000, Geology and Wine 2. A geological foundation for terroirs
also have links to glaciation. This is primarily due to two fac-           and potential sub-appellations of Niagara Peninsula wines, Ontario,
tors, worldwide lowering of sea level during maximum glacia-               Canada: Geoscience Canada, v. 27, p. 67-87.
tion and the locally abundant sediments produced by glaciers.
                                                                         Meinert, L.D., and Busacca, A.J., 2000, Geology and Wine 3: Terroirs of the
     A prime example of this is the Graves-Medoc region of                Walla Walla Valley Appellation, Southeastern Washington State, U.S.A.:
Bordeaux, France (Wilson, 1998). Outwash gravels from gla-                Geoscience Canada, v. 27, p. 149-171.
ciation in the Pyrenees Mountains along the French-Spanish               Meinert, L.D., and Busacca, A.J., 2002, Geology and Wine 5: Terroir of the
border and the Massif Central in central France overloaded                Red Mountain Appellation, Central Washington State, U.S.A: Geo-
the Garonne and Dordogne rivers leading to the Gironde Es-                science Canada, v. 29, (in review).
tuary, which itself had been enlarged and deepened by the                Moran, W., 2001, Terroir: the human factor: The Australian and New
lowering of sea level. Each period of glaciation produced its             Zealand Wine Industry Journal, v. 16, #2, p. 32-51.
own series of gravel outwash floodplains along the rivers and
                                                                         Wilson, J.E., 1998, Terroir: The role of geology, climate, and culture in the
the best (First Growth) vineyards are all on the same type of              making of French wines: Mitchell Beazley, London, UK, 336 p.
gravel. Names such as Chateaux Lafite-Rothschild, Haut-Brion,
Latour, and Mouton-Rothschild are well known to wine lovers              Wilson, J.E., 2001, Geology and Wine 4. The origin and odyssey of Terroir:
throughout the world and each of these estate vineyards are                Geoscience Canada, v. 28, p. 139-142.
located on these gravel mounds.
                                                                                             Tales of the Purple Grape
                                                                                                          Purple
     Less well known are the gravel outwash plains of the South          S. Spayd, Ext Food Scientist/Food Scientist, FSHN, WSU Prosser
Island of New Zealand. These were fed by the extensive al-
pine glaciation of the Southern Alps mountain range that                      By now the Casual Cellar Rat has waded through a num-
transects southern New Zealand. These gravels form the sub-              ber of the basic chapters of the text “Wine Chemistry for the
strate for many of the vineyards in the Marlborough area of              Conscientious Cellar Rat, Not for the Mouse at Heart” by I. M.
New Zealand and some of the wineries of this region focus on             Vino, the world renowned wine cellar rat. Today's chapter is a
the coarse gravels for their best vineyards (http://                     tough one, wine color. Fortunately, everyone who is anyone is
www.stoneleigh.co.nz/). Another area in New Zealand,                     either at VinExpo or the Enology meetings in some exotic land.
Gimblett Gravels, is perhaps the first viticultural region in the        This chapter is going to be a tough one. CCR thumbs through
world to specifically define itself on the basis of the gravel.          the chapter and sees lots of ugly looking chemical structures,
Legally, wines from this appellation have to consist of at least         but vows to tackle the subject. Of course, a glass or two of the
95% grapes grown on the Gimblett Gravels (http://                        latest vintage of Syrah will help considerably. CCR looks on that
www.gimblettgravels.com/index.htm).                                      as homework!

     Even though some vineyards in Washington State, France,                 Compounds contributing the color of red grapes and wines
and New Zealand share elements of terroir, there still are large         belong to a class of compounds called phenols. Not all phenols
differences in climate, culture, and viticultural practices that         in wines express color. The most simple phenol consists of a
make these areas distinct. The study of terroir does not aim to          benzene ring with a single hydroxyl group attached. Struc-
minimize these other factors or the importance of human in-              tures representing this simple phenol are shown in Figure 1.
genuity in making great wine from great vineyards (Moran,                CCR was never a big fan of organic chemistry, but realizes
2001) but simply to illustrate the importance of understanding           there are uses for it. Downing a swig of phenols, CCR struggles
the physical environment as one essential element of terroir.            on.

     As time permits we intend to continue our studies docu-                 Some of the simpler phenols in wine, CCR reads, are com-
menting the terroir of different viticultural areas in the Pacific       pounds called nonflavonoid phenols (Figure 2). Although these
Northwest. This research is aimed not only to document the               compounds are technically benzenes and not phenols, ben-
setting of individual vineyards but also to understand what              zoic acid, benzaldehyde, cinnamic acid, cinnamaldehyde, chlo-
elements of terroir are likely to be most promising for produc-          rogenic acid and tyrosol are often grouped with the


                                                                     4
nonflavonoid phenols in enology texts and will be included as             acylated. There are five anthocyanin aglycones found in Vitis
such in this discussion. Some of the nonflavonoid phenols in              vinifera grapes - cyanidin, delphinidin, peonidin, petunidin,
wines are from grapes while others are from oak, assuming                 and malvidin. As a side note, strawberries contain pelargonidin
the wine was aged in oak. There are different compounds within            and cyanidin. Expression of color and stability of the pigments
each general type of nonflavonoid phenol. Derivatives of ben-             depends upon the substituents in the R side groups. R1 is inevi-
zoic acid include vanillic acid and gallic acid, which are                tably a sugar group. Anthocyanins with a single sugar group,
hydroxybenzoates. Vanillic acid is present in oak aged wines.             at R1, are called monoglucosides. A second sugar group can
Gallic acid may be present due to the fruit and/or oak. Benzal-           attach at R2. Those anthocyanins are diglucosides since they
dehyde arises from either the grape or oak. The two related               have a sugar group at both the R1 and R2 positions. In
compounds, vanillin and syringaldehyde, are extracted dur-                monoglucosides, the substituent at R2 is a hydroxyl group. Vitis
ing oak aging. Most of the nonflavonoid phenols in wines are              vinifera grapes contain only monoglucosides, while French-
cinnamic acid derivatives, including p-coumaric acid, caffeic             American hybrids contain diglucosides, inherited from their
acid, and ferulic acid. These compounds, along with chloro-               American parent, in addition to the monoglucosides. Pinot noir
genic acid, originate from the grape with the exception of p-             fruit differs from other Vitis vinifera grapes in that none of the
coumaric acid and ferrulic acid which may also be derived from            anthocyanins are acylated. CCR thinks that is kind of cool. The
oak. These compounds can form esters with compounds such                  Head Cheese, rather Winemaker, will know if CCR screws up
as sugars, alcohols and organic acids. At this point, CCR de-             and pumps some Merlot into the batch of Oregon Pinot noir.
cides to check on the cooling systems of the tanks as it is start-        Acylation increases stability of anthocyanins. Also, diglucosides
ing to get warm in the cellar, or at least it feels that way.             are more stable against degradation, but are more susceptible
                                                                          to browning than monoglucosides
      Back from the tank check, CCR bites into the snack de jour,
Cougar Gold Cheese of course, and swigs on a bit of wine.                     Color expression by anthocyanins is dependent on many
Now it is time to tackle the "big boys", the flavonoid phenols!           factors. The type of substituent found on the aglycone funda-
Flavonoid phenols consist of two hydroxybenzene rings (CCR                mentally affects the color of the anthocyanin. Increasing de-
glances back at the previous page) which are attached by an               gree of hyroxylation (OH) on the C-ring increases the degree
oxygen-containing ring structure called a pyran (Figure 3).               of blueness, while increasing methoxylation (OCH3) increases
(GULP). Flavonols, flavan-3-ols, and anthocyanins are three               the degree of redness. CCR sees that Washington Merlot con-
general types of flavonoid phenols. CCR thinks that was all a             tains at least malvidin 3-glucoside, delphindin 3-glucoside,
mouthful and almost more than can be handled by a poor                    petunidin 3-glucoside, peonidin 3-glucoside and acetate and
little, but conscientious, cellar rat. Slowly turning the page, CCR       coumerate derivatives of each of them.
sees what Herr Professor Vino was talking about. Now multiple
                                                                               Wine and juice pH have a big impact on color expression
visions dance before CCR's eyes. Of course there would never
                                                                          of anthocyanins. CCR can relate to that from the bit of lab
be just one kind of these compounds so that life could remain
                                                                          work done. As pH decreases the color of an anthocyanin pig-
simple. In CCR's eyes, there are now not only three cats, but
                                                                          mented solution becomes more red (flavylium cation form). As
they all have full litters of kittens!
                                                                          pH increases the color becomes more blue (quinoidal base).
     The major flavonols found in grape tissues are 3-glucosides          What CCR did not realize was that at pH 3.4 to 3.6, 25% per-
of quercetin, kaempferol, and myricetin. These compounds are              cent or less of the anthocyanins in solution are in the red
believed to participate in copigmentation of anthocyanins re-             flavylium form. The remainder exist as a colorless "pseudo-base"
sulting in increased color stability in red wines. All three com-         unless they are polymerized. Additionally, anthocyanin stability
pounds require light for synthesis. Usually, these compounds              decreases with increasing pH. Color loss can also occur during
have other sugars or compounds attached to the aglycone,                  tartrate stabilization with anthocyanins deposited as a part of
nonsubstituted form. When other organic compounds are at-                 the argols.
tached, they are referred to as being acylated or acyl deriva-
                                                                               Polymerization of anthocyanins begins at least during fer-
tives, while those with sugars attached are glycosylated or glu-
                                                                          mentation and continues throughout ageing. Anthocyanins
coside forms.
                                                                          polymerize with flavonoid and nonflavonoid phenols as well as
     Flavan-3-ols in wines are derived from the grape. Examples           a myriad of other compounds. Polymerization stabilizes the color
of these compounds are catechin, epicatechin, gallocatechin,              of red wines. The earlier it occurs in red wine production, pref-
procyanidins, and the condensed tannins. Flavan-3-ol concen-              erably during fermentation, the better. Monomeric anthocya-
trations begin to increase significantly after 3 days of fermen-          nins are subject to bleaching by sulfur dioxide (Figure 5). Poly-
tation on the skins and seeds.                                            merized anthocyanins exhibit more color expression at a given
                                                                          pH and are resistant to bleaching by sulfur dioxide. As the
     Anthocyanins are perhaps the most readily visible form of            polymers grow larger and larger, the complex pigment will
flavonoid. CCR can relate to this as another slurp of Syrah is            begin to precipitate and is responsible, along with condensed
taken with a nip of cheese. Reading on, they are responsible              tannins, for the deposits (other than tartrates) at the bottom or
for the red and bluish colors of red grapes and wines. Malvidin           sides of bottled aged wines. As anthocyanins polymerize the
3-glucoside is the primary anthocyanin found in Vitis vinifera            color of red wines shifts from the reddish-to reddish blue hue
grapes. As with the flavonols, anthocyanin aglycones are rarely           of young red wines to the brick-red hue of mature wines, and
found without a sugar moiety(ies) attached and may also be                eventually, to the yellowish-brown of very aged or oxidized


                                                                      5
wines. This yellowing is due to the degradation of anthocya-
nins to chalcones which represents an "opening" of the pyran                                                                                          Shade of blue
ring joining the A and B rings.
    By now CCR's head is reeling from all this stuff on phenols                                                                          H                               OH                             OH
and anthocyanins, perhaps a bit from the Syrah. The day is                                                                     2’ 3’                           2’ 3’                          2’ 3’
                                                                                                                          1’    B                         1’    B                        1’    B
winding to an end. CCR still has much to learn about phenols.                                                        R         6’   5’
                                                                                                                                       4’
                                                                                                                                             OH       R        6’   5’
                                                                                                                                                                       4’
                                                                                                                                                                            OH   R            6’   5’
                                                                                                                                                                                                      4’
                                                                                                                                                                                                            OH
Today's chapter focused on color without touching upon sen-                                                                   H                                H                          OH
sory impacts on flavor or aroma (some phenols are aromatic).                                                          Pelargonidin                        Cyanidin               Delphinidin
CCR decides that today's lesson was pretty basic, but there                                                                                                                                             OCH3




                                                                                                                                                                                                                  Shade of red
were some take home messages.                                                                                                                                                                 2’ 3’
                                                                                                                                                                                         1’   B
                                                                                                                                                                                 R            6’   5’
                                                                                                                                                                                                      4’
                                                                                                                                                                                                            OH

1. Pay attention to wine pH for color stability and                                                                                                                                      OH
   expression of red wines                                                                                                                                                       Petunidin
2. Determine which viticulture and winemaking practices                                                                                                                                                 OCH3
   will help to improve the polymerization process as early                                                                                                                              1’
                                                                                                                                                                                              2’ 3’
                                                                                                                                                                                              B
                                                                                                                                                                                 R                   4’
                                                                                                                                                                                                            OH
   in fermentation as possible (CCR realizes that aspect was                                                                                                                                  6’   5’



   not covered in this chapter)                                                                                                                                                                            OCH3
3. The boss can tell if you screw up and mixed some other                                                                                                                            Malvidin
   variety with the Pinot noir or if you really screw up and
   get French-American Hybrids into the Vitis vinifera wines.                                           Figure 4. Effect of substituents on anthocyanin color (from: Braverman
                                                                                                                  1963)
                                                                                         C

                                                                                     C         C                                                                                               SO 3 H

                                                                                                                                              O   +                                  O
                                                                     or
                                 or                                                  C         C         HSO3- +
                                                                                          C

                 OH                                 OH                                   OH                 Figure 5. Bisulfite addition

     Figure 1. Hydroxybenzene


                                                                                                                                             Student Awards
                                                                                                        Charles Edwards, Professor, Food Science & Human Nutrition, WSU Pull-
                                                                                                        man
           COOH             CHO                CH=CHCOOH         CH=CHCHO
                                                                                                             For what is believed to be the first time ever at WSU, two
                                                                                                        students have won scholarships from the American Society for
                                                                                                        Enology and Viticulture in the same year. James Osborn and
                                                                                                        Jeff Bohlscheid (Ph.D. in food science) were awarded $1,000
       Figure 2. Nonflavonoid phenols
                  Figure 2. Nonflavonoid phenols                                                        and $2000, respectively, scholarships from ASEV. Congratula-
                                                                                                        tions to both students!!



                                                                                                                         Enology/Viticulture Education
                                                                                                        C. Edwards, Professor, Food Science & Human Nutrition, WSU Pullman
                      R1                              OH                                  R3
                           OH                              OH                                  R4
                                                                                                             WSU along with other colleges in the state has worked
                                                                                          B
HO          O
                           R2
                                HO           O                  HO
                                                                          A
                                                                                 O
                                                                                 +             R5
                                                                                                        very hard this past couple of years in assembling an education
                  OH                                  OH                                 OR1            program complete with new courses not previously taught.
      OH    O                         OH                                  R2    O                       Many of you know that the university now has an approved
     Flavonols                             Flavan-3-ols                        Anthocyanins
                                                                                                        option in Enology/Viticulture within the Horticulture Department.
                                                                                                        Several new and exciting classes will be taught in Horticulture,
     Figure 3. Flavonoid phenols                                                                        Food Science, and other departments support of this option
                                                                                                        including the recently approved Wine Microbiology and Pro-
                                                                                                        cessing (FSHN 465/565). It is planned that this and other courses
                                                                                                        will be available state-wide using distance means. WSU faculty
                                                                                                        are very excited about the future!



                                                                                                    6
                 New Viticulture Position
                     Viticulture Position                                   Riesling was recommended as the best variety for production
                                                                            in eastern Washington based on its excellent fruit quality and
     The President and Provost at WSU provided the Washing-
                                                                            relatively good winter hardiness.
ton Grape Industries with an early holiday present. In Novem-
                                                                                 Conversion of the industry to European wine grapes was
ber, bridging funds were provided by WSU’s Central Adminis-
                                                                            not immediate. Climatic conditions in eastern Washington were
tration to initiate a tenure-track Extension Viticulturist position.
                                                                            not considered amenable to production of European wine
The funds provided are to support the position until perma-
                                                                            grapes. Rainfall in the producing regions of eastern Washing-
nent funds are in place. An Extension Viticulturist is the high-
                                                                            ton is less than 10 inches per year in much of the area. Winter
est priority in the grape and wine industry’s initiative going to
                                                                            temperatures drop to less than -10oF every five to seven years.
the Washington State Legislature for the 2003 session. This gift
                                                                            In the depths of winter this temperature is very near the mini-
gives us about a two-year (plus) head start in putting into place
                                                                            mum temperature that most Vitis vinifera varieties can tolerate.
an individual who will play a key role in working with the state-
                                                                            Planting of European wine grapes started in the mid-1970’s.
wide industry. To provide mutual support, the position will be
                                                                            Riesling predominated these early plantings and remained the
located at WSU Prosser. The search committee is chaired by
                                                                            predominant variety through the 1980’s. As wine grape pro-
Dora Rumsey, Southeast Extension District Director. Members
                                                                            duction practices were refined and hardiness issues were more
of the committee are Ed Adams, Extension Director of Agricul-
                                                                            understood, Riesling was phased out in favor of less hardy, but
ture and Natural Resource Programs at WSU; Markus Keller,
                                                                            “the more desirable big three varieties” - Chardonnay,
Viticulturist WSU Prosser; Jack Watson, Chair Benton County
                                                                            Cabernet Sauvignon, and Merlot. These three varieties now
WSU Cooperative Extension; Sara Spayd, Food Scientist WSU
                                                                            dominate the industry. Out of about 28,000 acres currently
Prosser; Mike Concienne, Area Manager National Grape Co-
                                                                            planted to V. vinifera in Washington about 4,000 acres are
operative; and Roger Gamache, Gamache Farms. Please con-
                                                                            planted to Riesling. Demand for Riesling has actually increased
tact anyone on the committee if you know of a potential can-
                                                                            to a moderate degree during the past two to three years. Of
didate.
                                                                            the top four or five varieties planted, Riesling was the only vari-
     During the search, members of the industry will be asked               ety that increased in price per ton paid by wineries. However,
to participate in the process. Each candidate will present a                that price still represents only about 40% of the price paid for
seminar open to anyone wishing to attend. Also, there will                  some other varieties.
probably be an industry lunch meeting to provide a less for-
                                                                                  Site selection and varietal suitability to the site are the two
mal opportunity for interaction. Everyone who interacts with
                                                                            most important aspects of grape production. Every other pro-
the candidates is asked to complete an evaluation form to pro-
                                                                            duction decision is going to be a response to site and variety
vide input to the committee during its deliberations. We hope
                                                                            selection. In Washington, Riesling is often found in sites or ar-
to see you!
                                                                            eas of vineyards that are less suitable for production of the “Big
                                                                            Three” varieties. Riesling fruit and wine quality are best when
                Production    Washington State
       Riesling Production in Washington State                              vines are grown on well-drained (both water and air) sites of
This article was prepared for a presentation at the February 2002           moderate temperature. Return-stack heaters and, especially,
Ohio Grape and Wine Shortcourse. It was published as a Proceedings          wind machines are common fixtures in eastern Washington
paper. I thank those winemakers who contributed to its preparation          vineyards regardless of variety. These protective mechanisms
by responding to my questionnaire. Please let me know if a similar
                                                                            are used spring, winter and fall for protection from excessive
article on other varietal wines would be of interest.
                                                                            cold temperatures. In late fall, moisture in the top three feet of
S. Spayd, Extension Food Scientist/Food Scientist, Food Science & Hu-
                                                                            soil is brought to near field capacity. The moisture serves as an
man Nutrition, WSU Prosser
                                                                            insulation factor for the root system in order to protect it from
     Washington State now ranks second in the United States                 freezing. This lesson was learned the hard way during the win-
for both total grape production and wine grape production.                  ter of 1978-1979 when the ground was dry and froze to a depth
The modern Washington wine industry was instigated by the                   of 8-inches. Vines that went into that winter with dry soils did
removal in the mid-1960’s of a native wine tax that gave it an              not survive, while those that were in “wet” soils were insulated
economic competitive advantage. Until this period, Washing-                 and survived. The other lesson learned from that event was
ton wines were predominantly made from American and                         about planting depth. The California recommendation of 8-
French-American hybrid grape varieties. Unfortunately, many                 inches was tossed out. Vines are now planted to a depth of 12
of the wines were cheap and very poorly made. With the re-                  to 16-inches. I should point out that an overwhelming majority
peal, these wines could no longer compete with out-of-state                 of wine grapes in Washington are grown on their own-roots.
wine that were predominantly European wine grape varietals
                                                                                 Double trunks and bilateral cordons with spur pruning con-
and of much higher quality for the same price. A wine grape
                                                                            stitute the basic structure of most grapevines in Washington.
variety collection existed at WSU Prosser that had been planted
                                                                            The “sprawl” training system has been a long time standard
in the 1930’s. A major research effort was begun in the mid-
                                                                            in eastern Washington. It consists of a single cordon wire at
1960’s to evaluate these and additional selections. This collec-
                                                                            about 4 feet above the vineyard floor; and two wind catch-
tion was updated and upgraded with additional selections by
                                                                            wires positioned about one foot above the cordon wire, spread
Dr. Walter Clore. New selections were based upon the recom-
                                                                            about one foot apart. The wind wires are often fixed and shoots
mendations of Dr. Harold Olmo of the University of California
                                                                            are kept “stuffed” between these two wires. Growers have
at Davis. In 1975, the results of a 10-year study were published.
                                                                            shifted to vertically shoot positioned (VSP) trellises, using the


                                                                        7
same basic vine structure. The trellis now consists of the cordon           present. The range in water applied represents the degree of
wire and about four moveable foliage wires. The foliage wires               sand in the soils with application rate increasing with increas-
are vertically spaced about 8 inches apart and alternate be-                ing percentage of sand. A majority of wine grapes are irri-
tween sides of the vine. The wires are brought up as shoot                  gated with drip irrigation systems. Soil water measurements
length increases through the growing season, positioning the                are taken with either neutron probe or the newer TDR sys-
canopy in a vertical wall of foliage about six to seven feet high.          tems. Large growers may have their own instrumentation. There
Cordon wires may be about 3.5 feet high on some of these                    are consulting services that can be contracted to do these mea-
systems. If foliage exceeds the desired height, vines are topped            surements. Water is supplied through either impounded water
or hedged as needed. Basal leaf removal occurs after fruit-set              from irrigation district canals that deliver the water to the farm,
to insure that berries acclimate to sun exposure. Presently, to             wells (may also be used to supplement irrigation water), or in
reduce sunburn, there is a greater trend to not remove as many              specific areas pumped directly from the Columbia River. Im-
leaves from the west side of the canopy of N-S oriented rows                pounded water availability is in the canal system is dependent
and from the south side of E-W oriented rows. Additionally, a               on the winter snowfall in the Cascade Mountains. Impounded
“stuff and fluff” technique may be used with the VSP trellis.               water also has to provide for sufficient stream flows for fish and
The morning sun side of the row is managed (stuffed and                     is also used for generation of electricity. Well permits are re-
plucked) for maximum sunlight exposure, while the afternoon-                quired for farming operations. Currently, there is about a three-
sun side of the row is managed (fluffed and fewer leaves                    year backlog for well permits. They are becoming increasingly
plucked) for dappled sunlight in the fruit zone. A few other                difficult to obtain.
training/trellis systems are used in Washington. These are the
                                                                                Crop loads for Riesling range from three to 9 tons/acre
Fan, Scott-Henry, and Smart-Dyson or Smart-Ballerina systems.
                                                                            with an average yield of about 5 tons/acre. Vines are cluster
The fan system is found in older vineyards that were planted
                                                                            thinned from bunch closure through veraison. Just after
when multiple (greater than two) trunks were used as a hedge
                                                                            veraison, vines may be “green-thinned.” Clusters that have
against loss to winter injury. The latter systems are primarily
                                                                            not gone through veraison at that point are removed. During
used in a limited number of plantings. The advantages of the
                                                                            the summer, vines may be cordon suckered to reduce shoot
bilateral cordon system over these other systems are 1) it is
                                                                            crowding and crop loads and to further open the canopy to
easy to instruct workers on how to prune, and 2) it is easier to
                                                                            increase airflow.
mechanically harvest and preprune. Riesling is generally pruned
to 30 to 35 nodes/vine on two-node spurs. Most growers wait                      Vineyard floor management for Riesling and other variet-
until mid-February to prune the more winter tender varieties.               ies in Washington consists of either a fall-planted annual cover
February 16 is usually the date after which little winter injury            crop, such as winter wheat or rye, a low growing summer dor-
occurs. After Concord, Riesling is usually the first variety pruned         mant perennial, such as crested wheat grass, or weeds. Cover
due to its degree of winter hardiness. Node numbers are ad-                 crops are used mostly to reduce erosion, primarily wind ero-
justed to compensate for bud mortality in years of severe dam-              sion, since many of the soils are very fine silt-loams. Soil pH is
age.                                                                        generally six to seven. A half-inch calcium carbonate layer (cali-
                                                                            che) is found in most soils at a depth ranging from a few inches
     Water management through irrigation is the greatest tool
                                                                            to several feet. Soils are ripped prior to planting to disrupt this
that Washington has for managing vine, grape and wine qual-
                                                                            layer and any plow pans that might exist. Most of the soils are
ity in the vineyard. Most of the precipitation in eastern Wash-
                                                                            very low in nitrogen and organic matter. Application of nitro-
ington occurs after harvest in the fall and before bud break in
                                                                            gen fertilizer is about 20 to 30 pounds of actual nitrogen per
the spring. As I indicated earlier, in the late fall soil moisture is
                                                                            acre per year.
brought to near field capacity in the top three feet of soil. In
the spring, when irrigation water is available, soil moisture is                The predominant form of bunch rot control for Riesling is
determined and if necessary returned to near field capacity.                canopy management. Airflow through the canopy is consid-
Other than in very sandy soils, little to no irrigation water is            ered crucial for reducing the incidence of bunch rot. This is
applied until late June to early July. Soil and vine water status           done through proper irrigation and nutrition management,
are monitored as well as shoot growth characteristics. Shoot                canopy positioning, and leaf removal.
lengths of three to four feet are the goals for canopy size in
Washington. As the vine uses up its reservoir of soil water, shoot               For the purposes of this presentation, I surveyed Washing-
elongation slows and internode length shortens. Shoot tips of-              ton winemakers to determine their vinification practices. On a
ten are allowed to die, if shoot length is at or near optimum.              volume basis, the responses represented about 98% of the pro-
Another indicator of water status is tendril growth and turgid-             duction in the state. Winemakers indicated that flavor develop-
ity. Once the desired canopy size is achieved and shoot growth              ment in the fruit is the primary criteria for determining harvest
has ceased irrigation water is applied in quantities that par-              dates. Riesling grapes are harvested between 21 and 24oBrix
tially replace water lost through evaporation and vine use. Ac-             for traditional table wine styles. Depending on the vineyard
tual quantities applied depend upon soil type, air tempera-                 and year, fruit pH ranges from 3.00 to 3.30, while titratable
ture, wind and stage of vine development. Generally about                   acidity ranges from 3.0 to 10.0 g /L (expressed as tartaric acid).
40% of the water lost or used is replaced. Supplemental water                   Most of the Riesling in Washington state is mechanically
applications have been reduced during the past 20 years from                harvested and delivered to wineries in large gondolas. Smaller
about 20 to 30 inches in the 1980’s to about 10 to 20 inches at             producers require hand harvested fruit in containers ranging


                                                                        8
from 30-pound lugs to one to two ton bins or machine-har-                 Guidelines for Sampling Nematodes from Vineyard
vested fruit in the one to two ton bins. Time between harvest
and crush/press operations ranges from an hour to 24 hours,
                                                                                              Pacific Northwest
                                                                                       in the Pacific Northwest
depending on proximity of the vineyard to the winery. On av-              Dr. Ekaterini Riga, Nematologist, WSU Prosser and Dr. Jack Pinkerton,
erage, time between harvest and crush was about two hours.                USDA-ARS Horticultural Research Lab., Northwest Center for Small
A vast majority of the grapes are taken straight from the crusher         Fruit Research, 3420 NW Orchard Ave., Corvallis, OR 97330
to the press with pectinase added at some point either before                 Although these guidelines are appropriate for a wide range
or after the crusher. Both tank presses and membrane presses              of agricultural systems, as we accumulate data, over the next
are used with type dependent on the winery. A maximum pres-               couple of years, we will modify the guidelines to assist the grape
sure of two bars is used, while most winemakers indicated 1.5             growers with nematode sampling in Washington State and
bars as a norm. Press time ranges from 1.5 to four hours. Most            Oregon.
winemakers indicated a press time of two hours. Juice yield is
normally about 165 gallons/ton with a range of 150 to 180                      Sampling for Nematodes in a Pre-plant situation: If a site
gallons/ton reported. Juice is settled prior to inoculation. Sulfur       chosen to plant a new vineyard has had a perennial crop in
dioxide is usually not added until after primary fermentation is          the past 5 years or it has recently been fallow, soil samples
complete or the desired level of residual sugar is reached. If            have to be taken down to 3 feet. A similar sampling strategy
there is a relatively high proportion (but still below the level of       should be used when sampling soil from a field previously
rejection by the winery) of fruit with bunch rot, sulfur dioxide          planted to an annual crop known to be a good host for nema-
would probably be added prior to fermentation. A majority, by             todes that affect grapes. For example, potatoes and carrots
volume and number of winemakers, of Riesling juice is inocu-              may have root knot nematode, Meloidogyne hapla, popula-
lated with Epernay II yeast strain. Other yeast strains used, in          tions in the lower soil profile. Always check crop and manage-
order of number of respondents, are: Cote de blanc,                       ment record to determine if nematodes (that affect grapes)
Steinberger, Prise de Mousse, R2, DV10, Geiseheim, and AW27.              were found on any previous crops. Soil samples should be
Average fermentation temperature reported was 55oC with a                 taken from areas of the field where decline of the previous
range from 47 to 65oF. Average time to complete fermentation              crop has been observed. Samples also should be taken from
was estimated at four weeks with a range of 10 to 60 days. Post           areas of the field where differences exist. These include differ-
fermentation addition of sulfur dioxide was generally 45 mg/L             ences in cropping histories, soil textures, yield, watering re-
with a range of 15 to 50 mg/L. Only one of the wineries re-               gimes or management practices. A sample should consist of at
sponded that oak aging and malolactic fermentation were                   least 20 subsamples (cores) collected along a “w” pattern in
used. This was to produce a dry style of Riesling wine. Pro-              each area. The composite sample should be approximately 1
jected life expectancy of the wines averaged two to three years           pint (500 cc) to 1 quart. A soil sampling tube (1” diameter x
with a range of one to ten years.                                         15-18”) used for soil fertility sampling is an excellent tool for
                                                                          collecting nematode samples. Soil or soil + roots should be placed
    Some specific comments from winemakers regarding                      in a plastic bag properly labeled on the outside of the bag and
Riesling production were:                                                 stored away from sunlight, at 40 to 100C (or 400 to 500F).
1) “Site selection is important for good quality fruit.”                       Sampling for Nematodes in Established Vineyards: The
2) “Planted in well drained cool sites, excellent quality fruit           majority of plant parasitic nematodes are found around and in
   (and resulting wines) are relatively easy to produce.”                 the “feeder roots”. Therefore, samples containing both soil
                                                                          and roots should be collected to a depth of 12 to 18 inches in
3) “Different appellations bring different components to                  the vine row. In vineyards with drip irrigation, roots, and there-
   wine.”                                                                 fore nematodes, are concentrated in the soil under the emit-
                                                                          ters. Vineyards should be partitioned and sampled by the dif-
4) “It is an absolute winemaker’s delight, if not impossible to
                                                                          ferences noted in pre-plant recommendation. Routine samples
   screw-up.”
                                                                          should be collected in the same manner as pre-plant samples,
5) “We bottle as early as 60 to 70 days after harvest which in            at least 20 subsamples collected along and across vine rows in
   Washington means Thanksgiving.”                                        a 5 acre area. When differences in vine vigor are present, 10
                                                                          or more vines should be sampled within a weak area and a
6) “One of Washington’s better grape varieties.”                          corresponding set in the adjacent health or more vigorous area
7) “Very important grape for Washington in spite of current               of the vineyard. When diagnosing vines of low vigor, separate
   emphasis on reds. Will become more important as the va-                root samples should be collected. Do not sample from the top
   riety increases in popularity.”                                        1 inch of the soil. Collect a composite sample of at least 1 pint
                                                                          of soil.
     In conclusion, Riesling wines contributed much to the es-
tablishment of Washington as one of the premium wine grow-                     Be aware that nematodes are found in ‘hot spots’ i.e. they
ing regions of the world. Though plantings declined during                seem to aggregate in certain locations. For example, roots and
the 1990’s, Riesling is making a bit of a resurgence today. Un-           soil near one vine might contain few nematodes, while an
less global warming eliminates artic outbreaks, doubtful, Riesling        adjacent vine might harbor high population densities. So, it is
will remain a player in Washington's wine industry.                       possible to miss them if sampling is not done properly.



                                                                      9
     When to sample for nematodes: It is best and easiest to
sample for nematodes when the soil is moist, preferably within
a week after rainfall or irrigation. Sampling date will depend
on which nematodes are suspected and the nematode man-
agement options. Population densities of nematode species
vary through the year. Root knot nematode population densi-
ties usually are greatest in the fall, while dagger nematode
densities peak in the spring. However, high densities of dag-
ger were found when Washington vineyards were sampled in
August 2000. It is preferable to sample grapes around the
harvest period, because the densities of root-knot, ring and
lesion nematodes are usually high at this time. Sampling in the
late summer or early fall also allows adequate time to plan and
implement nematode management options, such as fall or
spring fumigation. Soil temperatures should be least 100C (or
500F) when sampling for nematodes. Therefore, the sampling
period extends from early spring to mid autumn in most re-
gions of the Pacific Northwest.
     Be aware that nematodes are found in ‘hot spots’ ie they
seem to aggregate in certain locations. For example, roots and
soil near one vine might contain few nematodes, while an
adjacent vine might harbor high population densities. So, it is
possible to miss them if sampling is not done properly. Soil or
soil + roots should be placed in a plastic bag properly labeled
on the outside of the bag and stored away from sunlight, at 40
to 100C (or 400 to 500 F).



                                                           Season    Perspective
                                              2002 Growing Season in Perspective
Sara Spayd, Ext Food Scientist/Food Scientist, FSHN, WSU Prosser
     Despite all of the foibles involved, members of the grape and wine industry remain interested in dissecting growing degree
days of the most recent season from the context of the body of growing degree day history. Although we sweated as we toiled
in the vineyards this year, the growing season of 2002 came out in the middle of the pack of years from 1954 to 2002. Cumulative
growing degree days in 2002 at the WSU IAREC Headquarters’ Unit totaled 2526, just 21 GDD above the mean of 2505 GDD
(Table 1). Data for 2000 and 2001 growing degree days were not covered in their respective year’s newsletter. Interestingly,
addition of the past three years' information to the long term average resulted in an increase, even if slight, in the mean value
of the number of GDD accumulated by the end of each month from April through October.

            Table 1. Cumulative monthly growing degree day statistics for the growing season of 1954 to 2002.

            Statistic           April       May        June        July      August      September         October
            Mean                86          357        809         1442       2043         2407                 2505
            Minimum             8           178        602         1173       1735         2110                 2171
            1st Quartile        51          295        706         1316       1912         2240                 2326
            Median              80          360        804         1450       2014         2406                 2472
            3rd Quartile        114         405        882         1514       2124         2512                 2645
            Maximum             198         589        1162        1841       2509         2855                 2997
            Std. Dev.           47          90         130         160        189          215                   229

    Tables 2 and 3 show the ten coolest and ten warmest years by month for this period using cumulative growing degree days
beginning April 1 to the end of the given month. Neither of the three most recent growing seasons cracked the bottom or top
ten in regard to GDD accumulation. Of these three years, 2002 came closest to breaking into the grouping of warmest years
towards the end of the growing season, while 2001 came close at the beginning of the growing season. The up-down nature of
the 2002 growing season temperatures resulted in deceptively “normal” or “average” GDD totals. Cool April and May weather
pushed 2002 towards the bottom of the rankings when looking for warmth. As a result of extremely warm weather in July and
August 2002, GDD pushed it towards the top of the pack.



                                                                    10
     The extremes of 2002 and the resulting near average number of GDD’s demonstrate why often GDD tell us little about the
growing season. You really need to examine “how we got there” rather than just that “we got there.” “There” being the end
of the growing season.


Table 2. Top ten coolest seasons ranked by cumulative growing degree days by month from 1954 to 2002.
Rank         April                May            June             July                August               September     October
        Year         GDD   Year         GDD   Year      GDD    Year          GDD    Year     GDD    Year       GDD     Year         GDD
1       1967         8     1955         178   1984      603    1955          1173   1955     1735   1954       2111    1954         2171
2       1970         21    1984         198   1975      631    1954          1185   1976     1748   1955       2120    1955         2210
3       1955         24    1974         227   1955      637    1999          1201   1954     1776   1964       2130    1959         2220
4       1984         26    1978         240   1954      644    1976          1243   1980     1785   1959       2130    1964         2226
5       1975         30    1975         242   1971      646    1984          1245   1964     1816   1954       2138    1984         2232
6       1958         38    1999         247   1999      649    1981          1252   1975     1819   1980       2146    1971         2240
7       1963         43    1964         249   1991      664    1971          1274   1959     1831   1971       2150    1975         2240
8       1964         43    1970         263   1976      667    1983          1293   1984     1848   1975       2164    1999         2244
9       1954         45    1967         271   1996      669    1963          1294   1962     1849   1976       2168    1980         2247
10      1972         46    1959         273   1964      674    1974          1297   1999     1852   1999       2179    1983         2271
2002    22nd         69    15th         304   22nd      790    35th          1509   32nd     2097   29th       2440    28th         2526


Table 3. Top ten warmest seasons ranked by cumulative growing degree days by month from 1954 to 2002.
Rank         April                May            June                 July            August          September               October
        Year         GDD   Year         GDD   Year      GDD    Year          GDD    Year     GDD    Year       GDD     Year         GDD
1       1987         198   1987         589   1992      902    1958          1841   1958     2509   1958       2855    1958             2997
2       1977         189   1992         544   1987      921    1992          1814   1992     2449   1987       2843    1987             2979
3       1990         173   1958         497   1958      922    1985          1766   1987     2387   1990       2824    1967             2942
4       1994         154   1994         490   1969      934    1987          1754   1985     2317   1998       2815    1992             2892
5       195          152   1985         490   1985      963    1998          1638   1998     2315   1967       2812    1990             2884
6       1992         149   1956         473   1986      972    1994          1636   1961     2301   1992       2753    1998             2877
7       1962         148   1993         469   1957      1010   1990          1634   1990     2294   1994       2725    1994             2806
8       1989         144   1957         447   1977      1072   1969          1582   1967     2274   1961       2575    1988             2751
9       1980         142   1966         432   1989      1156   1961          1578   1994     2258   1979       2571    1979             2739
10      1988z        140   1969y        424   1994 x    1162   1956 w        1548   1977 v   2243   1985 u     2571    1956 t           2673
2002    27th         69    34th         304   27th      790    14th          1509   17th     2097   20th       2440    21st             2526

         z
           By the end of April, 2000 was 11th warmest at 39 GDD and 2001 was 23rd warmest at 80 GDD (tied with 1979 and 1961)
        y
           By the end of May, 2001 was 11th warmest at 411 GDD and 2000 was 13th warmest at 405 GDD
        x
           By the end of June, 2000 was 14th warmest at 881 GDD and 2001 was 30th warmest at 774 GDD
        w
           By the end of July, 2000 was 14th warmest at 1513 GDD and 2001 was 28nd warmest at 1403 GDD
        v
           By the end of August, 2001 was 19th warmest at 2096 GDD and 2000 was 30th warmest at 2094 GDD
        u
          By the end of September, 2001 was the 11th warmest at 2534 and 2000 was 26th warmest at 2418 GDD
        t
          By the end of October, 2001 was the 16th warmest at 2619 and 2000 was 23rd warmest at 2492 GDD




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