New model helps Northeast grape growers predict spring frost damage

GENEVA, N.Y. – A new Cornell University-developed computer model that estimates the temperatures that cause freeze damage in a dozen grape cultivars can help growers respond to the potential impact of spring cold snaps.

The model, which is publicly available, allows Northeast users to input temperature data from their local weather stations and choose from 12 grape cultivars to get a prediction within a couple of degrees of accuracy on whether their vines and buds may have experienced freeze damage.

“If we have a freeze event that surpasses [a cultivar’s] cold hardiness level, then the bud dies and then you have an impact on harvest because the flower tissue is in the bud,” said Jason Londo, associate professor of fruit crop physiology and climate adaptation. “If you kill that bud, it won’t produce grapes for that season.”

The model was developed by Hongrui Wang, a doctoral student whom Londo advises.

Londo and colleagues measure cold hardiness on 12 different varieties every week of the winter at Cornell AgriTech. They have been collecting data since 2009, which has informed the model. But the data they have collected applies to just one location, so Wang developed an application that allows users to input their local weather data and then get a prediction for their area. 

With warming spring temperatures, buds begin to open and green tissue pushes out. “That tissue has a much higher water content,” Londo said, causing it to freeze at around 28 or 29 degrees Fahrenheit and making vines especially susceptible to spring frost events. “Going forward, if we were to have a cold event in March or April, users can go to our website look at the model and see whether it was cold enough to where they’re concerned.” 

Londo and colleagues are working with collaborators in Canada and across the Northeast to verify the model works everywhere. They are also trying to understand the genetics that may enhance cold hardiness and slow bud break.

“As the climate gets warmer, bud break comes earlier, but frost risk doesn’t go down,” Londo said. “We’re working to understand what happens when buds freeze in general so that we can come up with new technologies to give us mitigation methods as the climate gets more and more chaotic.”

For additional information, read this Cornell Chronicle story.

Cornell University has dedicated television and audio studios available for media interviews.

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