Ground squirrels and gophers can be terrible for vineyards.
That’s bad news for California, where workers harvested about 3,632 thousand tons of wine grapes from vineyards in 2021 alone.
Unfortunately, California ground squirrels and other animals can decimate a wine crop in days.
Here at Smith’s Pest Management, we specialize in safeguarding San Francisco Bay Area vineyards from animals.
In this post, we’ll discuss the top ways to protect vineyards from pests like squirrels and mice and how to keep them from coming back in the future.
Let’s dive in.
How Pests Damage California Vineyards
In California, pest damage usually isn’t evident in vineyards until the vineyard crop is almost ready for harvest.
That’s because some pests (like gophers and ground squirrels) attack the vines from below while others (like raccoons and possums) show up suddenly to feed on newly ripe grapes.
Gophers and ground squirrels can destroy the roots and trunks of vines, while raccoons, possums, deer, and birds destroy the vine shoots, leaves, and fruit of your plants.
The result can be devastating – especially if you’re dealing with the presence of several pests at once.
Because of this, effective vineyard pest management requires a holistic, multi-faceted approach that considers all the pests that may be present.
How to Protect Grapes from Animals
We know that animals eat grapes because they’re delicious, nutritious, and easy to prey on. The question, now, is how you can protect your vineyard crop.
Here are a few of our top tips:
Gophers
How do Gophers Damage Vineyards?
Gophers can easily destroy young grape plants.
As they gnaw on grapevine roots or trunks, they can create large patches of dead or dying vines.
As they tunnel underground to build their burrows, gophers can also damage the irrigation systems vineyards rely on.
How to Protect Vineyards from Gophers
It’s very hard to get rid of gophers in a vineyard when the vineyard management uses a disc or rototiller between the rows.
This is because the chopped-up, loose soil makes it very hard to set traps.
Many vineyards also plant a cover crop between the rows, which makes gopher control extremely difficult.
To control gophers, it’s essential to take action at the first sign of gopher activity (fresh mounds in the spring or fall, when the soil is moist).
Some common gopher control methods in vineyards include trapping, fumigation with aluminum phosphide, or hand-applied bait.
While trapping and hand-baiting can be used year-round, you should only apply aluminum phosphide when the soil is moist.
Ground Squirrels
How do Ground Squirrels Damage Vineyards?
Can squirrels eat grapes? Yes, and they often do!
Ground squirrels will wait until grapes are almost ready to move in rapidly and eat the entire crop in just a couple of weeks.
When the vineyard harvesting crew arrives, they are surprised to find no grapes to harvest.
How to Protect Vineyards from Gophers
It isn’t easy to get rid of ground squirrels when the grapes are ripe.
By the time vineyard crews notice pest predation, the squirrels are already attacking the crop. Unfortunately, almost nothing can be done at that time, and the crop is likely to be lost.
When it comes to controlling ground squirrels in vineyards, management actions depend on the activity patterns of the ground squirrels present and the time of year when the management action is taken.
Some common options include habitat modification (removing materials like vine trimmings and ground cover that ground squirrels may use as harborage), deep plowing along the perimeters of fields (which destroys burrow entrances), fumigants, baits, and traps.
Voles
How do Voles Damage Vineyards?
Voles damage vineyards by feeding around the root crown of young, vulnerable vines or chewing holes in irrigation lines.
In fact, voles can girdle or kill young vines in a matter of days. Voles are most likely to invade vineyards that plant cover crops, which provides them year-round cover.
How to Protect Vineyards from Voles
The best way to protect vineyards from voles is to keep their numbers low. Once vole numbers get out of control, bringing them back down is challenging.
Exclusion tactics can minimize vole damage, while bait applications can help control vole populations.
Destruction of vegetation, including ground cover, is also an effective way to reduce vole damage.
Since these animals only travel a few feet from their burrows to eat, removing vegetation will eliminate their cover and make the area less attractive to voles.
Rats
How do Rats Damage Vineyards?
Like ground squirrels and gophers, rats will eat ripe grapes, decimating a vineyard crop in just a few days.
How to Protect Vineyards from Rats
Controlling rat populations involves many of the same tactics as ground squirrel control. Viable options include habitat modification, trapping, baiting, and fumigating.
Raccoons
How do Raccoons Damage Vineyards?
Raccoons, like other pests in California, love sweet, tangy grapes.
And since raccoons are such crafty little creatures, keeping them out of vines can be challenging. They’ll push through crop netting, pick grapes from vines, and quickly destroy a grape crop.
How to Protect Vineyards from Raccoons
Management guidelines for raccoons can be challenging to achieve.
While netting may slow the raccoons down, it won’t keep them out of the grapes.
Instead, the only reliable method to prevent raccoon damage is erecting an electrified fence around the vineyard, which will exclude the pests.
Possums
How do Possums Damage Vineyards?
When berries begin to ripen, possums can easily climb vines to access them, damaging the plants in the process.
In most cases, the damage possums cause is localized but extreme, putting the survival of the vine at risk.
How to Protect Vineyards from Possums
To keep possums out of your vineyard, install electric fencing with a live wire located at the possum’s nose level – about 4-6” off the ground.
Utilizing cage traps baited with tuna fish or cat food is also an effective method to control possum populations.
How do Wildlife Control Experts Keep Animals Out of Vineyards?
Since keeping wildlife out of vineyards can be such a complex process, the easiest way to ensure success is to hire a wildlife control expert like Smith’s Pest Management.
Here’s what you can expect when you work with a professional team:
Pest Trapping
When you work with a professional wildlife and pest control team, trapping will be one of the most common pest removal approaches.
Trapping is especially effective in vineyard areas where pest populations are out of control.
Our team here at Smith’s can safely and humanely deal with various pest species, from ground squirrels to raccoons and possums.
Pest Exclusion
After trapping the target pests, it’s essential to keep them from coming back.
We provide pest exclusion recommendations to help you safeguard your vineyards and prevent further pest infestations.
Follow-Up Treatments
Once we’ve resolved your pest infestation, we’ll create a schedule for ongoing pest control treatments to prevent re-infestation.
This is the easiest and most convenient way to protect your precious grapes from pest damage.
Vineyard Pest Prevention Tips
Keeping pests out of vineyards can be difficult.
After all, grapes are so delicious and nutritious that it’s impossible to lure pests away with bait or other attractants.
Instead, you must protect the vineyards before the crop turns ripe.
Once a crop is lost, it’s essential to immediately start a heavy trapping and control program in the vineyard.
This is the only way to control the pests that would otherwise destroy the crop next season.
Here’s why that matters:
Once pests like ground squirrels have found a vineyard, they will ruin that vineyard every year – unless a year-round ground squirrel program is in place.
With these things in mind, it’s essential to implement a pest control and prevention program early and year-round in a vineyard until the vines are large enough that they can’t be killed by pests – usually five years or more.
Here are a few ways to keep pest species out of your vineyard once and for all:
- Keep deer, pigs, and bears out with adequate fencing. Deer, rooting pigs, and hungry bears can destroy a vineyard, especially if they enter the area early in the year and eat the young shoot growth of your vines. Fortunately, it’s easy to control these animals with fencing. Most pest control professionals recommend fencing that is 6-8’ high and made of woven wire. Adding a layer of electrical fencing outside the deer fence will also deter bears, raccoons, pigs, and other pests.
- Keep rodents at bay with traps and baiting. Gophers and other burrowing rodents can be effectively controlled via traps and baiting. This process requires expertise, patience, and effort, which is why it’s best left to a professional pest control team. Some vineyard owners also choose to use biological control methods, like the introduction of barn owls, to control voles, gophers, rats, and field mice.
- Use netting to deter birds. Birds are yet another pest species that can quickly destroy a vineyard. Fortunately, netting is an effective and accessible deterrent method. Over-the-row netting can cover large surface areas and reduce bird predation, while scare devices like motion-activated sprinklers can prevent birds from landing on vines.
- Deter a variety of pests with aromatic deterrents. Aromatic deterrents can work with other pest control methods to keep predation at bay. Planting strong-smelling herbs like mint, oregano, chives, sage, rosemary, and thyme can help upkeep rabbits and deer at bay without requiring the use of toxic repellents or poison bait.
Looking for Vineyard Wildlife Control in the San Francisco Bay Area? We Can Help!
Few things are more frustrating (or destructive) than pests in your vineyard.
Gophers, ground squirrels, voles, rats, mice, raccoons, birds, deer, and other pests can destroy a grape crop in a matter of days, leaving your vineyard in disrepair.
Fortunately, you don’t have to live with these pests forever.
Here at Smith’s Pest Management, we provide humane animal trapping and removal to help you protect your vineyards and say goodbye to pests. If your vineyard is located anywhere between Marin to Monterey — we can help!
