
084: Damage Control - Voles & Other Vertebrate Pests with Kelly Mulville & Newt Wimer
Vineyard UndergroundShow Notes
Voles, gophers, and ground squirrels are more than a nuisance — they can devastate vineyards if left unchecked. In this episode, host Fritz Westover sits down with Kelly Mulville of Paicines Ranch and Newt Wimer, an agricultural innovator, to discuss practical, sustainable ways to manage these vertebrate pests. Kelly shares his firsthand experience with a sudden vole outbreak at Paicines Ranch — one of the worst he's ever seen — and explains how quickly the damage escalated. He walks through the telltale signs of vole damage, how girdling kills vines, and why population cycles and rainfall patterns play a role in outbreaks. Newt provides insight into developing an organic-approved, non-poisonous control technology that uses liquid CO₂ to safely and efficiently manage underground pests without harming predators or soil ecology. Together, they emphasize that pest management must balance ecological health, economics, and innovation. Listeners will learn how combining predator support (owls, weasels), physical barriers, and new technologies can help reduce damage sustainably. The conversation also highlights ongoing efforts at Paicines Ranch to create regenerative systems that share successes and failures openly, helping the vineyard community at large. In this episode, you will hear: Voles, gophers, and ground squirrels can cause extensive vineyard damage, especially through girdling and root feeding.
Outbreaks are cyclical and may correspond with wetter years that promote vole breeding.
Physical barriers like vole tubes and underground fencing can protect vines—but must be properly installed and buried.
Encouraging natural predators such as owls and weasels significantly supports organic pest control.
New cryogenic CO₂ technology offers a fast, organic-approved, and cost-effective solution for underground pest management.
Follow and Review: If you enjoyed this episode, be sure to follow the podcast and leave a 5-star review on Apple Podcasts! Your support helps us reach more listeners. 💜 Click the '+' in the top right corner of Apple Podcasts to follow now. Resources: Come grow with Fritz through https://www.virtualviticultureacademy.com! Save $75 off your first year of membership with the code Underground at checkout. Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button. Listen to Kelly Mulville's previous episode – Episode 17: Using Sheep in Regenerative Agriculture with Kelly Mulville. Today's Guests: Kelly Mulville is a global agricultural consultant and the Vineyard Director at Paicines Ranch in San Benito County, California. Connect with Kelly at Paicinesranch.com Follow Paicines Ranch: Instagram: https://www.instagram.com/paicinesranch/ Facebook: https://www.facebook.com/PaicinesRanch/ YouTube: https://www.youtube.com/channel/UCXgoknCxuI2Y-w0CpjmOdug Newt Wimer specializes in product development for agriculture and developed the first organic-approved squirrel and gopher control device. Connect with Newt – Email Episode Sponsor: Thank you to SensorInsight for sponsoring today's episode. SensorInsight is a leader in vineyard soil moisture and weather monitoring. SensorInsight designs state-of-the-art, remote satellite monitoring of soil moisture and weather, bringing actionable information for your vineyard operations straight to your phone, with real-time data so you can best decide when to turn on your irrigation, how long to run the system, and learn how the dynamics of soil moisture can change over a given season. Visit them today at https://sensorinsight.io. And don't forget to mention the code Underground to receive a discount on your SensorInsight solution. Episode Credits If you like this podcast and are thinking of creating your own, consider talking to my producer, Emerald City Productions. They helped me grow and produce the podcast you are listening to right now. Find out more at https://emeraldcitypro.com. Let them know we sent you
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