Something is tearing up your garden. Varmints! But what kind?
In most parts of California, the likely culprits are moles, voles, or pocket gophers. Controlling these pests may take time and continued effort, but once you accurately identify your pest, you can keep them under control using non-toxic methods.
Moles (Scapanus species) are small mammals (4 to 7 inches long) that eat grubs, other insects, and earthworms. With oversized front claws, sensitive snouts, and poor eyesight, moles are adapted. They are terrific diggers. In a single day, a mole can crisscross a lawn with 150 feet of tunnels, and shallow feeding runs. Moles are most active after rain or irrigation when the soil is easy to work; they are less active during very hot or cold weather, or during drought. Their digging disturbs the soil and uproots plants, causing damage to gardens.
Moles (Scapanus species) are small mammals (4 to 7 inches long) that eat grubs, other insects, and earthworms. With oversized front claws, sensitive snouts, and poor eyesight, moles are adapted to life underground. They are terrific diggers. In a single day, a mole can crisscross a lawn with 150 feet of tunnels. Moles are most active after rain or irrigation when the soil is easy to work; they are less active during very hot or cold weather, or during drought. Their digging disturbs the soil and uproots plants, causing damage to gardens.
Voles (meadow mice) are rodents with short tails and round bodies. In California, we have six species of voles from the genus Microtus. The California vole (M. californicus) and the montane vole (M. montanus) are the most common garden pests in our state. Adult voles are 5 to 8 inches long, including the tail. Once you identify a vole problem, it’s important to get them under control quickly — vole populations can spike to several thousand per acre in a short time.
Voles are vegetarians. They feed on grasses, vegetables, herbaceous plants, bulbs, tubers, tree roots, and bark. Unlike moles and gophers, they’re not diggers, so they often take over abandoned gopher or mole burrows.
Pocket gophers (Thomomys species), commonly referred to as simply “gophers,” carry food and nesting material in furry cheek pouches, giving them their name. Gophers are larger than moles or voles — about 6 to 10 inches long. They have large yellow-orange front teeth and small eyes and ears. Like voles, they eat plants, preferring roots and the fleshy underground portion of plants. They’re very busy underground — a gopher’s burrow system can cover an area 200 to 2,000 feet square. A typical system includes feeding tunnels 6 to 12 inches below the surface, and nesting and food storage chambers as deep as 6 feet.
The Our Water Our World program doesn’t recommend poisons, fumigants, or incendiary devices to control moles, voles, or gophers.
Using barriers and traps are less-toxic, more humane, and more effective long-term than poisons or fumigants. Castor oil-based repellents may work temporarily but are not as effective as barriers or traps.
Call a professional if you plan to trap burrowing pests. Traps can be dangerous! They must be set properly and placed where they won’t harm children or pets. If you call a professional, be sure to ask them not to use poison baits or fumigants.
If you plan to set traps yourself, first identify the pest correctly and use a trap that is specific to moles, voles, and gophers. Be sure to follow the instructions on the label, in the packaging, or on the manufacturer’s website. To avoid serious injury, set traps in places where children or pets won’t disturb them or dig them up.
Many thanks to the University of California Statewide Integrated Pest Management Program for their excellent Pest Notes, from which we have borrowed much content!