Malbec, Sauvi B, Cab and Zinny may sound like a wine lover’s dream lineup, but they’re not varietals — they’re detector dogs, and they’ve just proven themselves to be California’s newest allies in the fight against grapevine disease. In a recent pilot project funded by the California Department of Pesticide Regulation, the quartet of canines was trained to identify two major threats to grapevines: vine mealybugs and leafroll virus.

The project, which concluded earlier this year, found that these specially trained dogs could detect infected vines with remarkable accuracy, offering a fast, non-invasive and cost-effective method of early disease detection.

Canine noses take the lead in early detection

The dogs were assigned two specific targets. Malbec, a black Labrador, and Sauvi B, an English Springer Spaniel, were trained to sniff out vine mealybugs — tiny insects that damage grapevines and spread viruses. Meanwhile, Cab, a German Shorthaired Pointer, and Zinny, another Springer Spaniel, focused on leafroll virus, a disease known to significantly impact grapevine productivity and wine quality.

The results of the trial were striking. Malbec and Sauvi B detected mealybug infestations with 97.3% accuracy, and ruled out the presence of infestation nearly 100% of the time. Similarly, Cab and Zinny achieved 93.4% accuracy in detecting leafroll virus, again with near-perfect rates of ruling out uninfected vines.

These results suggest that detection dogs can not only identify issues with high accuracy but can also help vineyards act before the disease spreads—without needing to remove or damage any vines in the process.

A cost-effective solution for vineyards

In addition to their impressive accuracy, the cost of using dogs in the vineyard appears surprisingly affordable. According to Wine Business, screening a 40-acre vineyard — roughly 27,000 vines — over two days with one handler and two dogs would cost approximately US$5,200. That equates to less than $0.25 per increase block vine, and under $0.01 per finished vine.

Stephanie Bolton, who led the pilot study as part of her role with the Lodi Winegrape Commission, said the goal was to develop an affordable, accurate, and real-time method of early detection that wouldn't harm the vines.

“Real-time, non-destructive early detection that’s affordable and accurate is exactly what the wine industry needs,” she explained.

Potential for widespread impact

The pilot project dogs were sourced from Canada and Hungary and underwent rigorous training before heading into the vineyards. Bolton believes their greatest value may lie not in established vineyards, but in vine nurseries, where detecting disease early is essential to preventing it from spreading.

“We are not going to get ahead of this challenge if we keep planting infested and infected vines,” she warned.

Leafroll virus and vine mealybugs are significant threats to viticulture worldwide. Once a vineyard is infected, containment is difficult and costly. Early detection — especially before planting — is critical to long-term vineyard health and wine quality.

Bolton and her team are now exploring options to secure ongoing funding for expanded canine training and deployment. Without financial backing, however, the dogs may be retrained for other scent-based roles outside the wine industry.

Sniffing out a sustainable future

As the wine industry faces increasing challenges from disease, climate pressure, and sustainability concerns, grapevine disease detection via trained dogs presents an innovative, scalable solution. These four-legged protectors offer more than novelty — they provide a real chance to safeguard vineyard health at a fraction of the cost of traditional methods.

So next time you raise a glass of California wine, spare a thought for Malbec, Sauvi B, Cab and Zinny — the unsung heroes making sure every vine starts life disease-free.