Vol. 14 No.2, March - April 1999
Dr. Tony K. Wolf, Viticulture Extension Specialist
I. Current situation:
Farewell: No, not me. We are, however, loosing our wonderful extension assistant, Dr. Imed Dami. Dr. Dami is moving to greener pastures as Viticulturist with the University of Illinois in Carbondale, IL. He will be departing Virginia in May. Dr. Dami joined our staff in November of 1997 after completing his Ph.D. at Colorado State University. Dr. Dami, like his predecessor Eric Capps, primarily assisted new and beginning grape producers, often on-site. But he also handled routine extension questions from experienced producers. He has helped with several production seminars and workshops and has had a small research project evaluating the use of dormant oil application to retard spring bud break. We will miss Imed, and wish him the very best with the development of the Illinois wine industry. The Virginia Winegrowers Advisory Board has approved continued funding for the extension assistant position and we are currently seeking qualified candidates to fill the position when Dr. Dami leaves.
1998 grape acreage and production figures: The Virginia Agricultural Statistics Service (VASS) recently released the 1998 grape crop production and acreage survey results. All commercial Virginia grape producers should have received a crop survey questionnaire in November of 1998. If not, please contact the VASS office at 804-771-2493 to let them know that you are a grape producer. Production in 1998 was 3,185 tons, up 8% from the 1997 crop (Table 1). The increase was due to slightly increased bearing acreage, as well as further yield recovery in vineyards which suffered from the severe freeze injury of February 1996. Chardonnay continues to lead production and acreage, but "other vinifera" -- varieties not separately listed in Table 1 -- showed the largest acreage increase between 1997 and 1998.
Grape Growing Task Force: Are you aware of the inter-agency Grape Growing Task Force? Initiated by the Virginia Department of Agriculture and Consumer Services (VDACS), the Task Force includes members of Virginia Tech, the Virginia Vineyards Association, and the Virginia Wineries Association. The mission is to increase public awareness of grape growing needs and opportunities in the Commonwealth. William Dickinson, Jr., Assistant Commissioner of Agriculture, and his staff in the agribusiness division of VDACS has led this campaign. Several meetings have been held in central areas of the state, including a well-attended meeting in Charlottesville on 1 April. Based on an industry survey that I conducted in 1996, as well as a more recent survey conducted by the wine marketing office of VDACS in 1998, Virginia wineries could dispose of approximately 1,000 tons of grapes per year above and beyond what they currently produce and/or buy. The number of wineries that are actively seeking additional purchase contracts ranges from around 10 to 18 per year (there are 52 wineries in the state). As with other eastern US states, there is a chronic shortage of high quality grapes, and opportunities do exist to have a profitable vineyard business. I do not, however, foresee a rapid saturation of the grape market in Virginia. In a 1986 magazine interview I made the optimistic prediction that Virginia's grape acreage might triple within 10 years. Acreage in that projected timeframe actually increased from around 1100 acres to a whopping 1400 acres hardly a tripling! The barriers that existed in 1986 remain. They are principally (a) the high capitalization costs; (b) existing land-owners recognition that her site is viticulturally unsuitable for grape growing; and (c) the cost and/or unavailability of labor to do the vineyard work. Look at vineyard acreage increases from 1997 to 1998 less than 50 acres if we're to believe the VDACS figures. I'm aware of another 100 acres or so of vineyards planned for 1999. But it will be some time before we reach the 400 to 500 additional acres that would be needed to sustain the fruit needs expressed by existing wineries. My point is two-fold: the opportunities remain good for industry entrants who can meet the challenging start-up requirements. Secondly, I would hope to allay the concerns of independent growers who foresee an impending glut of grapes.
Table 1. Virginia grape acreage and production for 1997 and 1998. Data obtained courtesy of the Virginia Agricultural Statistics Service, VDACS, Richmond, VA.
|Vitis vinifera winegrapes:|
|Other V. vinifera||197||249||322||462|
|Interspecific hybrid winegrapes:|
|Other interspecific hybrids:||65||61||99||63|
|Table grapes and others:||62||68||205||166|
*Totals may differ from actual column totals due to rounding of individual variety data.
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II. Early season pest management:
Cool weather during the week of 12 April is slowing the rapid increase in bud development that occurred the previous week. Chardonnay at the Winchester AREC are at full swell, with a leaf showing here and there. The following is a perennial reminder, taken from previous years¹ Viticulture Notes of pest management considerations for the period immediately prior to and after bud break. Text is updated to reflect current chemical control options.
A. Phomopsis cane and leaf spot: Phomopsis cane and leaf spot (Phomopsis) is a fungal disease that causes sporadic problems in some vineyards, chronic problems in others. Vineyards most at risk are those with a history of symptoms including the fruit rotting phase of the disease. Dead canes and spurs affected by Phomopsis can produce disease inoculum for several years. Spring symptoms are usually restricted to the first few internodes of young, developing shoots. The fungus produces elongate lesions, which give the base of the shoot a darkened, crusty appearance. The lesions can also affect fruit cluster stems and cause a shriveling of the immature berries. Foliar symptoms begin as numerous, small, greenish-yellow lesions that later blacken and may drop out causing a shot-hole effect. Affected leaves are usually distorted and eventually drop from the shoot. The Phomopsis organism overwinters in the bark of canes and spurs in fungal fruiting structures termed pycnidia. Pycnidia are abundant on the Phomopsis-scarred canes and spurs which had been infected as shoots in the spring. Rainfall and warm weather trigger a release of spores from the pycnidia. Spores are splashed to new shoots and, if unprotected, the shoots can be infected. Lesions appear three to four weeks after infection. Infections occur most commonly in the pre-bloom period; however, recent research by Dr. Mike Ellis at Ohio State University suggests that berry and rachis infections can occur well into the summer. This may explain why we can see an abundance of ripe fruit rot due to Phomopsis where abundant shoot infections occur. Phomopsis can reduce crop directly from loss of affected berries (either immature fruit in spring, or a ripe rot of mature grapes), or indirectly through weakened shoots.
Control: Phomopsis control in established vineyards commences with pruning. Infected canes and spurs are the source of inoculum. Research has shown that dead one-year-old wood can produce inoculum for several seasons, but that viable two-year-old, and older wood, is not a source. Therefore, be certain to instruct your pruners to make clean pruning cuts. Do not leave dead spurs or pruning stubs on the vine, particularly where there is evidence of Phomopsis lesions. Canes affected by Phomopsis are generally light-colored with small dark spots (pycnidia) visible on the internodes, although, as mentioned above, infected canes may or may not bear the elongate lesions typical of early season shoot infections. If possible, remove as much of this affected wood from the vine as possible. Protectant fungicides are necessary where Phomopsis is present. Mancozeb (e.g., Manzate 200, Dithane, Penncozeb) or Captan are currently recommended for Phomopsis control (Virginia Tech Grape Pest Management Guide). Ziram may also be used up until fruit forms, and is also an effective fungicide against Phomopsis. One or the other of these fungicides must be applied at label rates as soon as possible after bud-break, and repeated as disease conditions warrant. Repeated rains, cool weather, and a history of Phomopsis problems would all argue for shortening the protectant spray schedule in the early season to no more than 5 to 7 days between sprays. Abound (azoxystrobin) is registered for Phomopsis too. However, Dr. Wayne Wilcox mentioned at the January meeting in Roanoke that their experience in New York State illustrated that Captan or Mancozeb was superior to Abound for Phomopsis. Wilcox's 1997 data showed that vines treated with Captan (3 lb/acre) had 2% Phomopsis incidence on cluster stems (relative to untreated control), compared to 17% disease incidence on Abound-treated (11 fluid oz./acre) vines (Fung. Nema. Tests, Vol. 53). The work of Muza and Travis in Pennsylvania (reported in same publication) also showed that Abound was not superior to mancozeb (Penncozeb 75DF at 4 lbs/acre) for Phomopsis control on Niagara grapevines (very susceptible to Phomopsis). These reports would argue against using Abound specifically against Phomopsis in favor of the more dependable Captan or mancozeb. Bear in mind that any of these fungicides would have to be reapplied as shoots expand, and/or following rain erosion of applied materials.
B. Black rot: Black rot can result in significant fruit loss to the unwary, but is fairly easy to control in all but the wettest years. Varieties and species vary in their susceptibility to black rot, but most of our commonly grown vinifera and hybrid varieties should be considered highly susceptible. All young green tissues are susceptible to infection beginning with the onset of spring growth. Leaves are susceptible for about one week after unfolding; berries are susceptible until veraison. Symptoms appear on leaves as tan, circular lesions one to two weeks after infection. The lesions soon produce small black pycnidia, which release additional spores during wetting periods. The process of infection, pycnidia formation, and spore release is repeated throughout the spring and summer with favorable weather conditions. It is for this reason that it is crucial to avoid the primary infections. Berry infections cause direct fruit loss through shriveling and drying of the berries, which remain attached to the cluster stem (rachis).
Control: Cultural practices that aid black rot control include canopy ventilation as afforded by shoot thinning, shoot positioning, and selective leaf removal from fruit zones. The black rot fungus overwinters in mummified fruit from the previous season. Most of this residual fruit is on the vineyard floor, but some clusters remain on the trellis. It is helpful to remove these clusters at winter pruning. In addition to cultural practices, fungicides are necessary to avoid black rot development on most varieties. Fungicides must be applied starting early in the growing season. Most of the primary black rot inoculum is released pre-bloom so good fungicide coverage from bud break through bloom is critical for effective black rot control. Black rot fungicides include Ferbam, mancozeb, Captan, Bayleton, Nova, and Captan. Captan is rated as having only fair control of black rot and would not be a wise choice as the sole fungicide for black rot control. Nova and Bayleton offer protectant as well as eradicant properties against black rot. For effective eradicant action, the fungicides must be applied within 72 hours of the beginning of an infection period. Elite (tebuconazole) was recently registered on grapes and has black rot (and powdery mildew) fungicidal activity and efficacy similar to Nova. Due to its recent registration, it may be some time before supplies of Elite are available in Virginia.
C. Climbing cutworms: Climbing cutworms are the larval stage of several moth species. The larvae feed on swollen grapevine buds and can cause significant destruction of buds and recently emerged shoots. Injured buds appear hollowed-out, which is the same appearance of buds damaged by grape flea beetles. Cutworm larvae feed at night and seek shelter in soil and debris during the day. Thus, if you observe damaged buds, and cannot locate the pest, chances are that climbing cutworms are at work. Cutworm larvae are about an inch long. They are smooth, brown or gray, and have stripes running the length of their bodies. A quick search around the base of an affected vine can usually reveal the pest. Feeding begins in the spring when buds begin to enlarge. The extent of damage depends on the cutworm population but also on the duration of the bud-break stage. During cool springs, when the period from bud-swell to bud-break is delayed, damage can be extensive. Conversely, with hot weather at this stage, shoots emerge quickly and damage is minimal. Vineyards must be monitored carefully for cutworm feeding in the period around bud-break, and treated with an insecticide if feeding affects more than 2% of the buds. Many of the grape insecticides, such as Sevin, Dipel (Bacillus thuringiensis [B.t.]), and Guthion, are effective against cutworms (and grape flea beetles). Cutworm control can be improved by spraying in the late afternoon or early evening to ensure that fresh residues are present when feeding commences. Read the insecticide label to determine the correct rate of product application.
D. General pest management considerations: Powdery and downy mildew are also of concern in the period after bud burst. Downy is typically controlled by default if either Captan or mancozeb are included for black rot control. Powdery mildew will receive consideration in the next newsletter. The importance of adequate disease control in the pre-bloom period cannot be overemphasized. The pre-bloom period has at least three features contributing to increased disease pressure: (a) rapidly elongating shoots which present unprotected tissues; (b) large amounts of primary disease inoculum being discharged; and (c) temperature and moisture conditions favorable to disease development. We use a 7- to 10-day spray schedule from bud-break to fruit-set. Beyond that, we switch to a 10- to 21- day schedule. In general, the schedule is lengthened during dry weather and shortened during rainy periods. If we believe that a black rot infection period occurred towards the end of a schedule, we will use either Bayleton, Nova, or Abound within 72 hours of the start of the wetting period (temperatures of 60 to 85°F and continual wetting of 6 to 9 hours are sufficient to allow black rot infections).
All pesticides have specific limitations on their use, such as how much can be applied per acre per year, restrictions on use during the pre-harvest interval, and restrictions on vineyard reentry. Revised EPA Worker Protection Standards (review 1993 and 1994 newsletters) also affected pesticide labeling, particularly in regard to minimum re-entry intervals and posting of treated areas. You are required to read the pesticide label and abide by the directions stipulated on that label. Disease and insect management also requires more than just using the appropriate fungicide. Be certain that you have accurately calibrated your sprayer and that you achieve good coverage of vine foliage and fruit.
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III. Vineyard labor issues: Part 1:
Contributed by Ms. Lynette Wills, Farm Placement Specialist, VA Employment Commission Winchester, VA 22604, 540-722-3415, firstname.lastname@example.org
The following article is the first installment of a multi-part section on farm labor issues. The information is provided by Lynette Wills of the Virginia Employment Commission.
Introduction: I have worked as Farm Placement Specialist in the Winchester office for the past 14 years. My service delivery area includes the following counties: Fairfax, Loudoun, Prince William, Fauquier, Rappahannock, Page, Augusta, Highland, Rockingham, Shenandoah, Warren, Frederick and Clarke. There are 10 Farm Placement Specialists located in the following VEC office: Winchester, Danville, Petersburg, South Hill, Bristol, Warsaw, Charlottesville, Roanoke, and Exmore. Farm Placement Specialists provide a variety of services to Agricultural Employers and Migrant and Seasonal Farmworkers in the state of Virginia.
Among the services Farm Placement Specialists provide to agricultural employers are labor market information and assistance in recruiting both domestic local labor and recruitment of labor through the Agricultural Recruitment System. Assistance is also provided to employers regarding the H-2A program. The H-2A program allows agricultural employers who are unable to recruit sufficient domestic labor to harvest their crops, to request temporary alien agricultural workers. Forms and general information regarding either the ARS or H-2A programs may be obtained at VEC offices.
Additionally field sanitation, OSHA requirements, and Wage and Hour concerns may be addressed to any of the Farm Placement Specialists. While the VEC is not an enforcement agency we do work very closely with other state, regional, and federal government agencies and are often able to provide information regarding these and other issues. Employers are encouraged to contact the VEC with labor related questions. You may contact me directly or contact the appropriate VEC office if you are outside my geographical area of responsibility.
Labor Issues Facing Virginia's Agricultural Employers: A series of articles will begin with this issue of the newsletter, pertaining to labor issues facing agricultural employers who use the services of Migrant and Seasonal Farmworkers. Agricultural employers need to be aware of such issues as Field Sanitation, Federal Form I-9 Completion, Virginia New Hire Reporting, Farm Labor Contractor Registration and the Migrant and Seasonal Farmworker Protection Act.
The following definitions will pertain to this and all future issues:
Farmwork is work performed in agricultural production or agricultural service occupations for employers whose primary or secondary business activity is the production of agricultural products or the provision of agricultural services. For example, a pruner who works for a grape grower or a winery is performing farmwork, while pruning grape vines for a private homeowner would not be farmwork.
A Seasonal Farmworker is a person, who during the preceding 12 months:
A Migrant Farmworker is a seasonal farmworker who:
We will begin this series with information regarding the Federal Form I-9. The Immigration Reform and Control Act of 1986 requires "all employers" to verify employment eligibility of new employees. The Form I-9 is used to verify that persons are eligible to work in the United States. Employers must have on file a completed Form I-9 for every employee hired after November 6, 1986. As an employer you are required to:
Agricultural employers, agricultural associations, or farm labor contractors who employ, recruit or refer people for a fee also come under these requirements. Every time a person is hired to perform labor or services in return for wages or other remuneration, the Form I-9 must be completed, (exemptions to this requirement may be found in the Handbook for Employers).
If you hire a person for less than 3 business days, Sections 1 and 2 of the Form I-9 must be completed fully at the time of the hire‹when the employee begins work. If the employment will be for more than 3 business days, the employee must complete Section 1 of the form at the time of the hire‹when they begin work. Section 2 of the Form I-9 must be completed within 3 business days of the hire.
The Handbook for Employers as well as the Form I-9 may be obtained by contacting the United States Department of Justice, Immigration and Naturalization Services, Division of Consumer Affairs Outreach. Copies of the Handbook and Form I-9 may be ordered at (800)870-3676. Questions about the Employment Eligibility Verification process may be directed to the Employer Hotline at (800)357-2099. The Immigration and Naturalization Service web site: http://www.usdoj.gov/ins
Some of the most frequently found problems regarding the Form I-9 involve an employer's failure to complete and retain the I-9 form. Many employers are under the mistaken impression that employment eligibility verification does not apply to them specifically. All employers must comply with this requirement or face potential civil money penalties!
Another frequent problem involves clerical errors. Improper completion of the I-9 form such as failure to sign and date the form are often cited as problems by INS. While employers are not expected to be experts at judging a document's authenticity, employers are expected to put forth what INS considers to be a good faith effort. Upon examination of the document(s), if they appear on their face to be genuine, and to relate to the person presenting them, the employer must accept them. But if the writing on the document were upside down then the document would not reasonably appear to genuine, thus the employer must not accept the document.
The May/June newsletter will obtain information on field sanitation requirements. Information for this article was obtained from several sources including the Migrant and Seasonal Farmworker Protection Act and the Handbook for Employers. Additional information may be obtained by contacting any of the VEC's Farm Placement Specialists.
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IV. Upcoming meetings:
31 May - 2 June 1999
12th International Enology Symposium
3-12 June 1999, Post-conference tour through Quebec, Ontario and New York wine regions The association holds a meeting every 3 years in a different part of the world. The meetings bring together an excellent group of technical experts from around the world. It is a great way to hear what is going on in various parts of the world and to meet representatives from all these places. Part of the meeting is always a post-conference tour of the wine growing area. The site in Montreal and the post-conference tour were chosen to highlight developments in the wine industry in NE North America.
Contact: Thomas Henick-Kling, ph: 315-787-2277; fax: 315-787-2284; e-mail: email@example.com
16-18 June 1999
ASEV Annual Meeting
Reno Hilton, Reno, NV
American Society for Enology and Viticulture PO Box 1855 Davis, CA 95617-1855
Phone: 530-753-3142; fax: 530-753-3318
14-18 July 1999
Oak Symposium and ASEV/ES Annual Meeting
St. Louis, MO
We, 14 JUL 99: Symposium tour, visit an oak forest and barrel making facilities
Th+Fr, 15- 16 JUL 99: Oak Symposium Science, practical experience, and tastings
16 JUL 99: Trade Show and Technical Presentations, Annual Meeting of ASEV/ES
Sat, 17 JUL 99: Technical Presentations, Annual Meeting of ASEV/ES
Contact: Ellen Harkness, Purdue University
Phone: 765-494-6704; fax: 765-494-7953; e-mail: firstname.lastname@example.org
24 July 1999 (TENTATIVE)
Virginia Vineyards Association Annual Meeting
Concept is a motor-coach tour of 3 or 4 northern Virginia vineyards/wineries with speakers at each vineyard. Topics may include irrigation design, varieties, pest considerations, and unique features of the host vineyards. Stay tuned for details.
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"Viticulture Notes" is a bi-monthly newsletter issued by Dr. Tony K. Wolf, Viticulture Extension Specialist with Virginia Tech's Alson H. Smith Agricultural Research and Extension Center in Winchester, Virginia. If you'd like to receive "Viticulture Notes" as well as Dr. Bruce Zoecklein's "Vintner's Corner" by mail, contact Dr. Wolf at:
Dr. Tony K. Wolf
AHS Agricultural Research and Extension Center
595 Laurel Grove Rd.
Winchester VA 22602
or e-mail: email@example.com
Commercial products are named in this publication for informational purposes only. Virginia Cooperative Extension, Virginia Tech, and Virginia State University do not endorse these products and do not intend discrimination against other products that also may be suitable.
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