UC IPM Online UC ANR home page UC IPM home page


SKIP navigation



Vertebrates and Their Damage

On this page
  • Bark girdling and burrows
  • Sprinkler damage
  • Chewed fruit
  • Pocket gopher mounds
  • Vole runways
  • Fecal droppings

Look regularly in and around groves for vertebrate pests and their damage. Look especially for ground squirrels, pocket gophers, rabbits, and roof rats. Record the date and location of problem spots, such as by marking a map of the grove, using colored flagging or spray paint in the grove, or by using a hand-held GPS (global positioning system).

Names link to more information on identification and management.

Click on photos to enlarge
bark girdling and burrows
Bark girdling and burrows
Identification tip: California ground squirrels can chew bark and cambium virtually anywhere on trunks and limbs. Their burrow entrances (shown here) are open and about 4 inches in diameter, but can vary considerably. Pocket gopher girdling is usually hidden below ground. Rabbit chewing occurs within 2 feet of the ground. Voles gnaw no higher than about 2 inches above ground.
 Sprinkler damage
Sprinkler damage
Identification tip: Coyotes, gophers, and ground squirrels most commonly cause gnawed, leaky irrigation lines and emitters. Dogs, rabbits, and sometimes other vertebrates also chew irrigation systems.
Chewed fruit
Chewed fruit
Identification tip: Roof rats chewed this fruit. Opossums, raccoons, tree squirrels, and occasionally ground squirrels or other vertebrates also chew fruit.  The location and extent of chewed fruit and pattern of teeth marks help to distinguish the damaging pest species.
Infestation evidence

 Pocket gopher mounds
Pocket gopher mounds
Identification tip: A pocket gopher infestations is evidenced by loose mounds of soil, sometimes in the shape of shallow volcanoes, but with no distinct opening. Gophers themselves are rarely seen above ground. When only tunnels are seen, determine whether digging may be due to moles. Moles feed mostly on insects and earthworms and do not damage citrus.

Vole runways
Vole (meadow mouse) runways
Identification tip: Trails of eaten vegetation and shallowly mounded thatch in grassy weeds and ground covers are evidence of voles.

Fecal droppings
Fecal droppings
Identification tip: The size, shape, and abundance of excrement droppings help you to identify the vertebrate species in your grove. Rabbits scatter coarse, circular fecal pellets. These jackrabbit pellets are each about 1/2-inch in diameter. Cottontail pellets average about 1/4 inch.

Top of page

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2016 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   /PMG/C107/m107bpvertdmg.html revised: June 24, 2016. Contact webmaster.