This presentation will provide information on, and initial experiences from, a project that is trialing and evaluating the effectiveness of an agro-thermal heat treatment machine to reduce the impacts of temperature extremes and increasingly variable temperatures on wine grape production in the Okanagan. Through a partnership with UBC Okanagan, the project is looking at how agro-thermal heat treatment affects three issues that directly impact yield, quality and management costs for the wine industry:
- extreme and variable temperatures during critical grapevine phenological stages that determine fruit set and final yield
- fungal disease pressure, which increases under variable wet and warm conditions
- extreme winter freezing events that increase the severity of bacterial diseases, such as crown gall of grapevines
Agro Thermal Heat Treatment of Grapevines in the Okanagan, Chad Douglas, Quails' Gate Estate Winery
1. Agro-thermal heat treatment of
Grapevines in the Okanagan
Chad Douglas - Viticulturist, Quails’ Gate Estate Winery
2. Agro-thermal heat treatment of
Grapevines in the Okanagan
What are the challenges/concerns for winegrape growers in a changing
climate?
What are some approaches to mitigate these concerns?
Agro-thermal Systems – how does heat treatment (thermaculture) fit into this?
Quails’ Gate Estate Winery 2019
FAIP Project
3. Challenges/issues for vineyards in a
changing climate?
Concern: Loss of varietal character – what does this mean?
Once vineyard is established limited options to mitigate climate
Warming and more extreme climate trends
Plant vineyards to cooler sites;
higher latitude, higher altitude, northern aspects
= greater climatic risk ie. Frost, winter damage
4. Challenges/issues for vineyards in a
changing climate?
Concern: Yield and ripening consistencies
Grapevines very sensitive to temperature during key phenological stages
Flowering and fruit-set;
poor or uneven set
Veraison - Ripening/maturation of grapes
Low or high brix and sugar, unbalanced fruit and wine
5. Challenges/issues for vineyards in a
changing climate?
Concern: Increased Disease pressure
Specifically powdery mildew and botrytis
Increased rain events, higher humidity = increased disease pressure
Rotate chemistries, practice better IPM
Spray more
Rely on Chemical companies to formulate new products
6. Challenges/issues for vineyards in a
changing climate?
Concern: Sustainability issues
Fungicide and pesticide resistance
FRAC: Group 3, 11 chemistries in-particular.
Pesticide applicator health and safety
Cost of fungicides, cost of increased number of sprays
Residual fungicides/pesticides in wine
7. Agro-thermal Systems – how does heat
treatment fit into this?
How does it work;
Propane operated, hydraulic fan heater, generating 350+ degrees F hot air
Video https://www.youtube.com/watch?v=cRDt7jlN930
Instantaneous Heat Shock – activates plants self-defense mechanism
Claims state; heat results in:
Increase flower bud pollination; increase number of berries set = increase yield
Impact and kill fungal and bacterial spores
Increase plant phenol and antioxidant properties
Costs; propane approx. $8/ac + tractor driver @ 3.5mph
My experience in Oregon
2014-15 Growing seasons; Yield and botrytis trials
8. Quails’ Gate Estate Trials 2019
- 2 year trial in collaboration with UBCO
1. Botrytis cinerea; Chardonnay 3 treatments
Conventional program (1 botryticide)
Heat treatment only
Control – no botryticide, no heat
2. Vine metrics; Merlot treated vs non-treated
Yield, brix, pH, TA, others…
1st year results: No significant difference
3. Crown-gall – Agro-bacterium Vitis;
In-conjuction with other trail treatments in block
9. Quails’ Gate Estate Winery 2019
- other applications.
1. Ripening – increase brix
Cabernet Sauvignon in Northern Okanagan
3 applications after veraison
Crop-load: 3.6 T/a Brix: 25.4 (no-control)
2. Powdery Mildew
New lease - organic vineyard
Large population of over-wintering spores – black canes
6 x Sulphur + 5 x Heat = ZERO Mildew and Botrytis
3. Wine phenolics
Merlot block; treated vs non-treated
Juice panel to assess; tannin, anthocyanin
Formal tasting and evaluation to come
10. Agro-thermal heat treatment of
Grapevines in the Okanagan - Summary
Climate trends are warming with more extremes
Known challenges for winegrape farmers
Strategies to mitigate these challenges
Is Agro-thermal heat treatment one of them, another tool to add?
Technology claims need to be validated… we hope to do that.
Thank-you
BC Agricultural Climate Adaptation Organization
Quails’ Gate Estate Winery
UBCO; Louise Nelson, Tanja Voegel and their team