Lawn Care/Basics for Homeowners-Lawn Care/Pest Control/Burrow
Burrowing lawn rodents of the insectivore family, such as moles, do absolutely no damage to the actual turfgrass plants themselves. On the other hand pocket gophers are rodents and love to eat turfgrass roots. These two animals do have one thing in common though. They are responsible for tunneling and burrowing through the soil, and creating headaches for millions of homeowners. Trying to control these pests is a problem within itself because of their random burrowing patterns.
The common mole is a small, grey, furry, burrowing insectivore about 5 to 8 inches in length. Its head has a long, tapering snout. It lacks external ears and has tiny, barely detectable eyes. The most distinguishing feature of the mole is its stubby, broad, shovel like front feet, which are well adapted to digging.
Moles
live underground and seldom venture out of their burrows. They are most active
early in the morning and late in the evenings. The ridges produced by their
burrowing plainly indicate their presence. Most of the tunneling is done in
a random search for food, so many of the tunnels are seldom re used. This is
important to remember when trapping moles. Their more permanent or "active"
tunnels run along fences, borders or other protected places that lead to feeding
areas.
Moles feed almost exclusively on soil insects: earthworms and grubs are the most important food sources. Because they eat insect pests, they can be beneficial. A mole has a tremendous appetite and can consume nearly half its own weight in food daily. Roots are not a target food source, but may be damaged indirectly as moles dig through the ground in search of grubs and earthworms.
Often there is no need to control moles. However, when they become a nuisance, satisfactory control measures are available. The two most promising methods are trapping and reducing insect populations in the yard so the moles forage for food elsewhere.
Two
types of traps are generally available: harpoon and choker loop traps. (See
manufacturer's instructions.) When properly placed in yard, these traps provide
the simplest and most effective means of control. For trapping to succeed, it
is vital to select a frequently used tunnel. To locate active tunnels, cave
in short sections of several burrows by pushing down on them with your foot.
Be sure to indicate each site with a stick or marker. Moles are very suspicious
and avoid areas that appear odd, so don't disturb the tunnels more than necessary.
Check each marked site and place traps in the tunnels which have been rebuilt.
If there is no catch within a day or two, change locations and reset the trap.
Moles invade areas in search of food, so they can be discouraged by your treating
turf to reduce insect populations. However, do not
expect moles to immediately leave; time and patience are required. Several insecticide materials are available for grub control.
Many moles, however subsist primarily on earthworms, so that may or may not
be effective.
Repellents such as mothballs inserted into the tunnels may drive moles elsewhere, but this method is only practical in a small area. Poison baits and gassing are dangerous and generally ineffective. They should not be used around a home yard.
Poison baits are too dangerous to children, pets, and other non target animals, and should not be used around a home yard. Drowning moles with a soap/castor oil mixture or use of vibration devices are not effective in eliminating moles.
For further discussion of moles and their control, see the following websites:
(Alabama) http://www.aces.edu/department/ipm/mole.htm
(Illinois) http://www.urbanext.uiuc.edu/hortihints/0106a.html
(Iowa) http://www.extension.iastate.edu/newsrel/1999/aug99/aug9914.html
(Michigan) http://www.msue.msu.edu/msue/imp/modwl/11209807.html
(Missouri) http://muextension.missouri.edu/explore/agguides/wildlife/g09440.htm
(New York) http://www.cce.cornell.edu/suffolk/grownet/sm animal/moles.htm
(Ohio) http://ohioline.osu.edu/w fact/pdf/0011.pdf
(Wisconsin) http://cf.uwex.edu/ces/pubs/pdf/G3200.pdf
Gophers are often confused with moles, but these are members of the rodent family. A wide variety of other animals are colloquially referred to as gophers, especially fellow rodents such as ground squirrels and voles. Curiously, a Floridian land tortoise is called a "gopher", presumably because of its habit of excavating tunnels for shelter. Even more strange, the southeastern United States gophers are called "salamanders!"
Recognizing Gopher Tunnels and Mounds
How can we tell one animal from another, particularly if sightings are rare, as with subterranean animals? The easiest method is to distinguish them based on evidence they leave on the surface, usually mounds, but also more subtle signs. Mounds shaped like fans or kidney beans are characteristic of gophers. Adjacent to the mound, where the handle of the mound would be, is nearly always a distinct soil plug. Gophers create mounds of this shape by pushing excavated soil up an inclined shaft like little bulldozers. Frequent comings and goings may develop mounds of a horseshoe shape, or they may even come full circle, suggesting a mole mound to the untrained eye. Also, gopher mounds tend to be clustered, often edge to edge, while those of moles usually show greater separation. Mole mounds are circular in outline and conical like a miniature volcano. But gophers also develop plugs that appear as solitary round mounds. These plugs are closed surface feeding access points or evidence of repair in a shallow tunnel. Finally, gophers may also leave one or more tunnels open to the surface, especially during wet or hot weather. These vents are made, presumably, to cool or dry the tunnel system.
Gophers excavate tunnels by loosening the soil with their long, curved
front claws and, when necessary, by employing their chisel shaped incisors.
Gophers line in a sealed burrow system, as shown by the plug at the base of
each mound. By sealing the system they deter invasion by unwanted guests and
survive heavy rain or even temporary flooding. Water is able to enter a tightly
plugged burrow only from below. The diameter of tunnels is strongly correlated
with the size of the gopher that dug it, though later residents may be smaller.
Gophers are strict vegetarians, using wide variety of plants for food. They are opportunistic feeders, collecting succulent food above ground near the entrance of feed holes, feeding on roots from below, or, when necessary, feeding above ground on woody vegetation and even cactus. During the growing season gophers are especially fond of bulbs and the fleshy roots of perennial weeds and grasses. In winter they clip woody roots and will even leave the security of the burrow to dine on the top growth of woody plants.
Gophers have external fur lined cheek pouches, which they use in gathering and transporting food. These pouches, which can be turned inside out, are on both sides of the jaw. Another adaption to their underground existence is their furry lips, which close firmly together behind the exposed and projecting incisors, enabling them to cut roots without ingesting soil. This unusual anatomical arrangement gives gophers a serious case of buck teeth. Amazingly, the gophers lower incisors grow nearly twice as fast as their upper teeth; the lower incisors of some species can grow an astonishing seventeen and a half inches a year, while the upper incisors may grow nearly nine inches. Considering the difficult work to which pocket gophers put their incisors, it is fortunate that they are capable of such remarkable growth. The teeth are worn down and honed by constant work in the soil.
Gophers are highly territorial and extremely intolerant of one another, regardless of gender and age, except during breeding season. Therefore, it is possible for just one gopher to be causing most of your problems.
Controlling gophers can become an obsession. Adventurous gardeners and assistant greenskeepers have developed a variety of methods. However, only two are time and cost effective: trapping and poison bait.
The surest, safest, and most humane method of controlling gophers is trapping. Many kinds of traps are available. Chinch traps are the most effective and come in a range of sizes to accomodate different species and tunnel sizes. When trapping any animal pest, one of the most important considerations is matching trap to pest. After that, success depends on the trapper. Don't be afraid to break new ground in developing improved techniques. The use of "come hither" baits such as fresh carrot or potato have show remarkable success early and late in the season when succulent plants are in short supply.
Registration and availability of poison baits varies by state. It is important to read and follow instructions on the label. The most effective and commonly used baits contain potent organic poison strychnine. This material is dangerous and must be used with great caution to avoid unintentional or secondary poisonings. Other registered materials include the acute toxicant zinc phosphide, which is less effective than strychnine; arsenic trioxide, on which there is little published information; and chlorophacinone, an anti coagulant labeled only for hand baiting.
For further information on gophers and gopher controls, see the following website: