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School Ground Invasion by Pocket Gophers
University of Nebraska—Lincoln Extension
Pocket GophersUsed with permission from University of
California StatewideIPM Program, J.K. Clark, photographer
Pocket Gophers are rodents
Up to 12 inches long and average ½ to ¾ poundNebraska has two species
Plains (Geomysbursarius)-most of NebraskaMountain (Thomomystalpoides)-extreme NW and SW Nebraska
Photo: University of Nebraska
Pocket Gopher Biology
Solitary except for mating and raising young Mating 1-2 times a year Litter sizes 3-4 young/SpringYoung disperse above ground in fall and usually at night
Pocket Gopher BiologySenses
Poor hearing and eyesightHighly developed sense of touchFossorial-live underground
HabitatSoil firm enough to maintain tunnelsAvoids rocky soils and swampy soils
The “Pocket” GopherOn either side of the mouth lies a fur-lined pouch that is used to carry stems, leaves, and roots
Some people misapply the word “gopher” to ground squirrels
Drawing: University of Nebraska
Underground BulldozersPocket gophers have oversized front limbs and clawsMore than a ton of soil can be moved each year Photo: University of Nebraska
Drawing: University of Nebraska
Photo: University of Nebraska
ID of Pocket Gopher Mounds
Gophers create mounds 12-20 inches in diameter
Drawing: University of Nebraska
Photo: University of Nebraska
Mole vs. Gopher Mounds
Only Moles Create Surface Runs
Gophers DON’T create runsGophers ONLY create mounds
Photo: Thomas Olander
Signs of Pocket GophersMounds of soil occur most often during early Spring and FallSizes of mounds are 10 to 20 inch in diameter One gopher can build over
200 mounds in a year!
Photo: University of Nebraska
A Pocket Gopher has a complex underground system
Root ZoneFrost-free
zone
Top View
Side View
75 to 100 feet
Drawing: University of Nebraska
Winter Soil Castes
Caused when a gopher excavates soil to the surface into snow tunnelsThis usually occurs under deep, long-lasting snow
Photo: University of Nebraska
Damage to Lawns and Equipment
Mounds cover grassDestroy plastic and rubber piping 2.8” in diameter or smaller
Photo: University of Nebraska
Photo: University of Nebraska
Damage to PlantsUnderground roots up to 4 inches in diameter can be severedGirdling may occur at or below ground Photo: University of Nebraska
Excluding Pocket Gophers Around Flower Beds, Trees, or Shrubs
Build an underground fence of ¼ or ½ inch galvanized wire meshBury at least 18 inches
Excluding Pocket Gophers Around Buried Utility
Cables or Irrigation TubesTrenches can be filled to surround the pipe with 6 inches of large gravel (> 1 inch diameter)Use conduit or pipe diameters > 2 7/8 inches
Cultural Practices to Deter Gophers
Flooding often kills gophers or sometimes discourages them from diggingApply weed control to those species that produce large, attractive roots
Best if done for 2 straight years
Repellents for Gophers
NoneQuestionable effectiveness of predator odors, sonic devices, and botanicals
Trapping SafelyWear appropriate safety equipment, such as gloves when handling traps and animalsAvoid setting traps in areas with high human/pet trafficCheck traps daily. Don’t set them if you can’t check them the next day
Pocket Gopher Control Solutions
There are a wide variety of traps on the marketPlace them below mound in opened tunnel. They can then be left open or closed, depending on preference
Drawing: University of Nebraska
Gopher traps: A. Macabee® type; B. Victor®Gopher Getter; C. Death-Klutch®-1; D. Box-type
Setting Gopher TrapsLook for the freshest moundFind the soil plug in itNow remove the soil with a trowel
Photo: University of Nebraska
Photo: University of Nebraska
Photo: University of Nebraska
Setting Gopher Traps Always place
traps below groundAlways wire-tie them to a stakeYou may use lure baits (carrots, fresh alfalfa) behind trapsDrawing: University of Nebraska
Pocket Gopher Control: Toxicants
Follow Label InstructionsTHE LABEL IS THE LAW!
Methods of Poisoning Pocket Gophers
Alternative 1 —toxicants placed below mound in tunnel through hand baiting
ORAlternative 2 —fumigants placed below mound in tunnel
Probes for Pocket Gophers
Probes are rods used to help find gopher tunnelsProbes can be simple homemade rods or professionally manufactured ones Photo: University of Nebraska
Three Methods of Hand Baiting
Hand baiting through mound
Use of probe with bait applicator
Probing and baiting
Drawing: University of Nebraska
Hand Baiting ToolsTools may include:
A probe to locate the mound plug
12-inch No. 9 wireLong-handle screwdriver
A garden trowelA small funnel with tube extension to dispense bait A flag to mark the mound
Photo: University of Nebraska
Choosing Toxicants for Pocket Gophers
Zinc phosphide has been shown to be slightly less effective than strychnine
Photo: University of Nebraska
Gopher Toxicant TypesAnticoagulants, chlorophacinone(RoZol®) and diphacinone (Eaton's Answer®)These multiple-dose toxicants require a greater amount of bait than zinc phosphide or strychnine
Fumigants for Pocket Gophers
Most effective whenSoil is moistSoil is a loam or clayTunnel system is small (new)
Gophers may sense gas and push soil between it and themRetreating tunnels are often necessary
Resources/InformationInternet Center for Wildlife Damage Management
http://icwdm.orgPrevention and Control of Wildlife Damage
http://icwdm.org/handbook/index.htm#omLocal Cooperative Extension/Pesticide Education Office
Learn more about becoming a Licensed Pesticide Applicator. Only necessary for Restricted Use Pesticides (Wildlife Damage Control Category 14)
CreditsContent Specialists
Dennis Ferraro, UNL Extension in Douglas-Sarpy County Stephen Vantassel, UNL ExtensionDallas Virchow, Wildlife Services, USDA-APHIS
Content EditorErin Bauer, UNL Extension
PhotosDennis Ferraro, UNL Extension in Douglas-Sarpy County
CreditsPhotos cont.
Stephen Vantassel, UNL ExtensionDallas Virchow, Wildlife Services, USDA-APHISJ.K. Clark, University of California Statewide IPM Program (http://www.ipm.ucdavis.edu)Thomas Olander
CreditsArtwork/Graphics
UNL ExtensionUniversity of California Davis (http://www.ipm.ucdavis.edu)
