Grape Weed Control Harlene Hatterman-Valenti North Dakota State University The Northern Grapes Project is funded by the USDA s Specialty Crops Research Initiative Program of the National Institute for Food and Agriculture, Project #2011-51181-30850
Vineyard Floor Management Goals Weed control yet soil conservation Control vine vigor and wine quality Sustainability! Integrated approach
Vineyard Floor Management Tools Cultivation Herbicides Cover Crops Mulches
Traditional Resurgence Advantages: Eliminates surface crusts Enhances N mineralization Disadvantages Soil compaction Soil structure loss Risk of vine damage Spread of soil pests and pathogens Cultivation
Often restricted to vine row Limited # available Advantages Cost effective Efficacy on perennials Precise timing of competition Disadvantages Risk of toxicity (plant/man) Herb. Resistant weeds Herbicides
Herbicides for new plantings Preemergence Devrinol Gallery Princep (half rate) Prowl (others) Snapshot Surflan (others) Treflan (others) RUP pdts not included Postemergence Aim Fusilade DX Goal (others) Poast Reglone Rely 200 Roundup (others) Scythe Select (others)
Preemergence Casoron Chateau Devrinol Goal (others) Karmex (others) Matrix FVN Princep Prowl (others) Solicam Surflan (others) Treflan (others) Herbicides for Established plantings Postemergence Aim Poast Rely 200 Roundup (others) Scythe Venue RUP pdts not included
Under the trellis study - NY Compared no weed control to high-level herbicide treatment Herbicide treatment results: Concord grapes pruning weights doubled. Yield increased 67%
Row-middle strategies No vegetation Herbicides Cultivation Grass Mow Cover crops Complex system.
Pool et al., 1998
Evaluating Annual Under-Vine Cover Crops to Reduce Vegetative Vigor and Improve Wine Quality of Riesling and Cabernet franc Justine Vanden Heuvel Associate Professor Department of Horticulture Cornell University
Excessive vegetative vigor is a problem A vegetation-free zone is kept in undervine rows Previous studies using perennial under-vine cover crops have reduced vine vigor (Hatch et al., 2011) Current Practices
Objective: To test the use of annual under-vine cover crops in Riesling and Cabernet franc vineyards Hypothesis: Cover crops will introduce competition with vines for water and nutrients, resulting in reduced vegetative vigor and maintained/improved fruit and wine quality.
Experimental Design Riesling (2011, 2012) Annual Rye Grass Buckwheat Natural vegetation Glyphosate Control Cabernet franc (2010-2012) Annual Rye Grass Buckwheat Turnip Root pruning Glyphosate Control
Riesling
Cabernet franc Control Annual ryegrass Buckwheat Turnip
Vegetative Growth Data Collection Shoot and lateral growth rates Petiole nutrient analysis EPQA Pruning weights Predawn and Midday Water Potentials Fruit and Wine Quality Number and weight of clusters per vine Berry weights Juice characteristics (Brix, TA, ph, YAN) Fermentation profiles Sensory analysis
Winemaking 2 lots per treatment Standard white wine protocol Whole cluster pressed Yeast strain EC 1118 Sensory Testing Difference Consumer preference
Shoot Growth Rates
Cane Diameters
Harvest Yields 2011 No significant differences in total clusters per vine, total cluster weight per vine, berry weight in 2011
Harvest Yields 2012 2012 had no significant difference in berry weight or total number of clusters per vine In 2012, the total weight of clusters was less for the ARG treatment than the control
Harvest 2011 and 2012 Juice characteristics
Rate and duration of shoot growth in Cabernet franc C = control, AR = annual ryegrass, BW = buckwheat, RP = root pruning, TP = turnip
Yield components, crop load, fruit composition in Cabernet franc - No significant differences in soluble solids, TA, ph and anthocyanin concentration were found among treatments
Reduction in vine vigor was related to reduced water availability to the vines associated with AR and RP C = control, AR = annual ryegrass, BW = buckwheat, RP = root pruning, TP = turnip The asterisk indicates significant differences with respect to the control based on Dunnett s test at P < = 0.05
Wine sensory analysis Consumer preference ranking test - Rank sum analysis for the 2010 vintage showed no preference for any specific wine produced in 2010 ( p > 0.05) Projective mapping test - Multiple factor analysis (MFA) was used to provide information about the perceptual differences between wines C Wine sensory analysis BW RP TP TP AR RP BW - Duplicates were not grouped together AR C
Conclusions Under-vine cover crops: eliminated the need for herbicides had little or no impact on vine growth and fruit composition in Riesling reduced mid-day water potential in Cabernet franc, improving cropload and reducing vine pruning weight had no perceiveable impact on wine sensory scores in Cabernet franc
FIN Questions? Acknowledgements: Lindsay Jordan, Michela Centinari, Taryn Bauerle, Thomas Bjorkman, Hans Walter-Peterson, Mike Colizzi, Anna Katharine Mansfield, Wagner Vineyards,
Herbicide Injury Main concern herbicide drift http://oregonstate.edu/weeds/articles/em8860.pdf (Preventing herbicide drift injury to grapes.) http://www.oznet.ksu.edu/library/hort2/mf2588.pdf (Questions and answers about vineyard injury from herbicide drift.) http://www.ksda.gov/includes/document_center/pesti cides_fertilizer/drift/prev_horm_damage_grapes.pdf (Preventing hormonal-type herbicie damage to Kansas grapes.)
2,4-D Injury
Glyphosate Injury
Documenting suspected herbicide drift www.ag.ndsu.edu/pubs/plantsci/weeds/a657w.htm Record all possible information Consider all possible causes. Make a map of the area. Take many high-quality photographs. Crop damage usually assessed 15-30 days later. Use yield loss estimates to predict amount of damage. Promptly contact all parties and insurance companies involved to validate collected information. State laws may require additional actions
Identify the problem
A closer look
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