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http://cecalaveras.ucdavis.edu/pocket.htm

Pocket Gophers

Pocket gophers are burrowing rodents that get their name from the fur-lined external cheek pouches, or pockets, they use for carrying food and nesting materials. They are well equipped for a digging, tunneling lifestyle with powerfully built forequarters, large-clawed front paws, fine short fur that doesn’t cake in wet soils, small eyes and small external ears, and highly sensitive facial whiskers to assist movements in the dark. An unusual adaptation is the gopher’s lips, which can be closed behind the four large incisor teeth to keep dirt out of its mouth when it is using its teeth for digging.

IDENTIFICATION:
Although they are sometimes seen feeding at the edge of an open burrow, pushing dirt out of a burrow, or moving to a new area, gophers for the most part remain underground in the burrow system.

Mounds of fresh soil are the best sign of gopher presence. Mounds are formed as the gopher digs its tunnel and pushes the loose dirt to the surface. Typically mounds are crescent- or horseshoe-shaped when viewed from above. The hole, which is off to one side of the mound, is usually plugged. One gopher may create several mounds in a day. In non-irrigated areas, mound building is most pronounced during spring or fall when the soil is moist and easy to dig. In irrigated areas such as lawns, flower beds, and gardens, digging conditions are usually optimum year round and mounds can appear at any time.

BIOLOGY AND BEHAVIOR:
Pocket gophers live in a burrow system that can cover an area of 200 to 2,000 square feet. The burrows are about 2.5 to 3.5 inches in diameter; feeding burrows are usually 6 to 12 inches below ground, whereas the nest and food storage chamber may be as deep as 6 feet. Gophers seal the openings to the burrow system with earthen plugs. Short, sloping lateral tunnels connect the main burrow system to the surface and are created during construction of the main tunnel for pushing dirt to the surface.

Gophers do not hibernate and may be active at any hour of the day. Gophers usually live alone within their burrow system, except for females with young or when breeding, and may occur in densities of up to16 to 20 per acre.

Gophers reach sexual maturity at about 1 year of age and can live up to 3 years. Females produce one to three litters per year: in non-irrigated areas, breeding usually occurs in late winter and early spring, resulting in one litter per year, whereas in irrigated sites, up to three litters per year may be produced. Litters usually average five to six young.

Pocket gophers are herbivores, feeding on a wide variety of vegetation, but generally preferring herbaceous plants, shrubs, and trees to grasses. Gophers use their sense of smell to locate food. Most commonly they feed on roots and fleshy portions of plants they encounter while digging. However, sometimes they feed aboveground, venturing only a body length or so from their tunnel opening. Burrow openings used in this manner are called “feed holes. “ They are identified by the absence of a dirt mound and a circular band of clipped vegetation around the hole. Gophers will also pull entire plants into their tunnel from below. In snow-covered regions gophers may feed on bark several feet up a tree by burrowing through the snow.

MANAGEMENT:
To successfully control gophers, the sooner you detect their presence and take control measures, the better. Most people control gophers in lawns, gardens, or small orchards by trapping them and/or by using poison baits.

Trapping
Trapping can be a safe and effective method to control pocket gophers. Several types and brands of gopher traps are available. The most commonly used is a two-pronged pincher trap, such as the Macabee trap, which is triggered when the gopher pushes against a flat vertical pan. Another popular trap is the choker-style box trap.

To set traps, locate the main tunnel with a probe. Use a shovel or garden trowel to open the tunnel wide enough to set traps in pairs facing opposite directions. By placing traps with their openings facing in opposite directions, a gopher coming from either end of the burrow can be intercepted. The box trap is easier to use if you’ve never set gopher traps before, but setting it requires more excavation than if you are using the Macabee trap, an important consideration in lawns and some gardens. Box traps are especially useful when the diameter of the gopher’s main burrow is small (less than 3 inches) because to use the Macabee-type wire traps, small burrows must be enlarged to accommodate them.

It is not necessary to bait a gopher trap, although some claim baiting gives better results. Lettuce, carrots, apples, or alfalfa greens can be used as bait. Place the bait at the back of a box trap behind the wire trigger or behind the flat pan of a Macabee-type trap. Wire your traps to stakes so they can be easily retrieved from the burrow. After setting the traps, exclude light from the burrow by covering the opening with dirt clods, sod, cardboard, or some other material. Fine soil can be sifted around the edges to ensure a light-tight seal. If light enters, the gopher may plug the burrow with soil, filling the traps and making them ineffective. Check traps often and reset them when necessary. If a gopher is not caught within 3 days, reset the traps in a different location.

Baiting with Toxic Baits
The key to an effective toxic baiting program is bait placement. Always place pocket gopher bait in the main underground tunnel, not the lateral tunnels. After locating the main gopher burrow with a probe, enlarge the opening by rotating the probe or inserting a larger rod or stick. Following label directions, place the bait carefully in the opening using a spoon or other suitable implement that is used only for that purpose, taking care not to spill any on the ground surface. A funnel is useful for preventing spillage.

Strychnine-treated grain bait is the most common type used for pocket gopher control. This bait generally contains 0.5% strychnine and is lethal with a single feeding. Baits containing anticoagulants are also available. They require a large treatment so that the bait is available for multiple feedings. Although generally less effective than strychnine baits, anticoagulant baits are preferred for use in areas where children and pets may be present. When using either type of bait, be sure to follow all label directions and precautions.

After placing the bait in the main burrow, close the probe hole with sod, rock, or some other material to exclude light and prevent dirt from falling on the bait. Several bait placements within a burrow system will increase success. Tamp down existing mounds so you can distinguish new activity. If new mounds appear for more than 2 days after strychnine baiting or 7 to 10 days after anticoagulant baits have been used, you will need to rebait or try trapping.

Biological Control
Predators, including owls, snakes, cats, dogs, and coyotes, eat pocket gophers. In most cases they are unable to keep pocket gopher populations below the levels that cause problems in gardens and landscaped areas because just one gopher can cause considerable damage. Predators rarely, if ever, remove every prey animal, but instead move on to hunt at more profitable locations. In addition, gophers have defenses against predators. For example, they can escape snakes in their burrows by rapidly pushing up an earthen plug to block the snake’s advance.

Recently there has been interest in the idea of attracting barn owls to an area for gopher control by installing nest boxes. Although barn owls prey on gophers, their habit of hunting over large areas, often far from their nest box, and their tendency to hunt areas with abundant prey, makes them unreliable for gopher control. When a single gopher, capable of causing damage rapidly, invades a yard or garden, a gardener cannot afford to wait for an owl to arrive. Effective action, usually trapping or baiting, must be taken immediately.

Follow-up
Once pocket gophers have been controlled, monitor the area on a regular basis for reinfestation of the land. Level all existing mounds after the control program and clean away weeds and garden debris so fresh mounds can be seen easily. It is important to check regularly for reinfestation because pocket gophers may move in from other areas and damage can reoccur within a short time. If your property borders wildlands, vacant lots, or other areas that serve as a source of gophers, you can expect gophers to reinvade regularly. Be prepared to take immediate control action when they do; it is easier, cheaper, and less time-consuming to control one or two gophers than to wait until the population builds up to the point where the gophers are causing excessive damage.

http://cecalaveras.ucdavis.edu/soaps.htm

INSECT CONTROL WITH SOAPS AND DETERGENTS
Soaps have been used to control insects for over 200 years. Recently, there has been a great increase in interest and use of these products. This change is doe to a better understanding of how to use soaps most effectively for pest control and a desire of many consumers to try insecticides that are easier and safer to use than many currently available alternatives.

How soaps and detergents kill insects is still poorly understood. In most cases, control results from disruption of the cell membranes of the insect. Soaps and detergents may also remove the protective waxes that cover the insect, causing death through excess loss of water.

Soap and detergents act strictly as contact insecticides, with no residual effect. As a result, to be effective sprays must be applied directly to, and thoroughly cover, the insect.

Several insecticidal soaps are produced and distributed for control of insects and mites. Available under a variety of trade names, the active ingredient of all is “potassium salt of fatty acids”. As such, they are similar chemically to liquid hand soaps. However, there are many features of commercial insecticidal soap products that may distinguish them from dishwashing liquids or soaps that are sometimes substituted. Insecticidal soaps sold for control of insects: 1) are selected to control insects; 2) are selected to minimize potential plant injury; 3) are of consistent manufacture.

Some household soaps and detergents also make effective insecticides. In particular, certain brands of hand soaps and liquid dishwashing detergents can be effective for this purpose. These are also substantially less expensive. However, there is increased risk of plant injury with these products, as they are not selected to be used on plants. (Dry dish soaps and all clothes-washing detergents are too harsh to be used on plants.) Also many soaps and detergents are poor insecticides. Identifying safe and effective soap-detergent combinations for insect control requires experimentation. Regardless of what product is used, soap-detergent sprays are always applied diluted with water, typically at a concentration of around 2 percent or 3 percent Table 1.

Soap - Detergent Sprays
Most research with insecticidal soaps and detergents has involved control of plant pests. In general, these sprays are most effective against most small soft-bodied arthropods, such as aphids, young scales, whiteflies, psyllids, mealybugs, and spider mites. Larger insects, such as caterpillars, sawflies, and beetle larvae generally are immune to soap sprays. However, a few large insects, including boxelder bugs and Japanese beetles, are susceptible.

Insecticidal soaps are considered selective insecticides because of their minimal adverse effects on other organisms. Lady beetles, green lacewings, pollinating bees and most other beneficial insects are not susceptible to soap sprays. Predatory mites, often important in control of spider mites, are an exception, a beneficial group of organisms easily killed by soaps.

One of the most serious potential drawbacks to the use of soap-detergent sprays is their potential to cause plant injury (phytotoxicity). Certain plants are sensitive to these sprays and may be seriously injured. For example, most commercial insecticidal soaps list plants such as hawthorn, sweet pea, cherries, and plum as being sensitive to soaps. Portulaca and certain tomato varieties also are sometimes damaged by insecticidal soaps. the risk of plant damage is greater with homemade preparations of household soaps or detergents. When in doubt, test soap-detergent sprays for phytotoxicity problems on a small area a day or two before an extensive area is treated.

Plant injury can be reduced by using sprays that are diluted more than the 2 percent to 3 percent suggested on label instructions. Also, wash plants within a couple of hours after the application to reduce leaf injury. Limiting the number of soap applications can also be important, as leaf damage can accumulate with repeated exposure.

However, because of the short residual action, repeat applications at relatively short intervals (four to seven days) to control certain pests, such as spider mites and scale crawlers. Also, application must be thorough with complete wetting of the pest. This usually involves spraying undersides of leaves and other protected sites. Insects that can not be completely wetted, such as aphids within curled leaves, will not be controlled. Environmental factors also can affect use of soaps. In particular, soaps (but not synthetic detergents) are affected by the presence of minerals found in “hard” water, which results in chemical changes producing insoluble soaps (soap scum). Control is decreased if hard water sources are used. Insecticidal soaps may also be more effective when applied during periods when drying is not overly rapids, such as early or late in the day.

Soaps and detergents can offer a relatively safe and easy means to control many insect pests. However, there are limitations and hazards associated with their use, as with all pesticides. By understanding these limitations, and carefully following all label instructions, these products can be used optimally.

http://cecalaveras.ucdavis.edu/vinegar.htm

FLAVORED VINEGARS AND OILS

Flavored vinegars and oils add excitement to salads, marinades and sauces. They also make special gifts, provided a few simple precautions are followed. Of the two, flavored vinegars are easiest and safest to make. Because vinegar is high in acid, it does not support the growth of Clostridium (C.) botulinum bacteria. However, some vinegars may support the growth of Escherichia (E.) coli bacteria. Infused oils have the potential to support the growth of C. botulinum bacteria; therefore, these products may cause great harm if not made and stored properly. By following the procedures below, both types of products can be safely prepared and used.

FLAVORED VINEGARS
Pre-preparation
Containers. Select and prepare containers first. Use only glass jars or bottles that are free of cracks or nicks and can be sealed with a screw-band lid, cap or cork. Wash containers thoroughly, then sterilize by immersing the jars in a pan of hot water and simmering for 10 minutes. Once jars are sterilized, remove from the simmering water and invert on paper towel to dry. Fill while the jars are still warm.

Herb vinegars.
Commercial companies that make herbal vinegars dip the herbs in anti-bacterial agents that are not readily available to consumers. As an alternative, briefly dip the fresh herbs in a sanitizing bleach solution of 1 teaspoon household bleach per 6 cups (1-1/2 quarts) of water, rinse thoroughly under cold water and pat dry. For best results, use only the best leaves and flowers, eliminating any brown, discolored, trampled or nibbled parts of the herbs. Fresh herbs are best picked just after the morning dew has dried. Allow three to four sprigs of fresh herbs or 3 tablespoons dried herbs per pint of vinegar.

Fruit, vegetable and spice vinegars.
Fruits often used to flavor vinegars include strawberries, raspberries, pears, peaches and the peel of oranges or lemons. Allow the peel of one orange or lemon or 1 to 2 cups of fruit per pint of vinegar flavored. For variation, try fruits in combination with herbs or spices. Vegetables, such as garlic cloves and jalapeno peppers, can also be used to add zest to vinegars.

Thread these on thin bamboo skewers for easy insertion and removal. Thoroughly wash all fruits and vegetables with clean water and peel, if necessary, before use. Small fruits and vegetables may be halved or left whole; large ones may need to be sliced or cubed.

Vinegar selection.
Use only high quality vinegars. Even the strongest herbs cannot diminish the sharp flavors of some vinegars. The type of vinegar to use as the base depends on what is being added. Fruits blend well with apple cider vinegar. Distilled white vinegar is best with delicate herbs and wine vinegar works well with garlic and tarragon. Do be aware, however, that wine and rice vinegars contain protein that provides an excellent medium for bacterial growth, if not stored properly.

Preparation
To make flavored vinegars, place the prepared herbs, fruits or spices in the sterilized jars, being careful to avoid over-packing the bottles. Use three to four sprigs of fresh herbs, 3 tablespoons of dried herbs or 1 to 2 cups of fruit or vegetable per pint of vinegar to be flavored. Heat vinegar to just below boiling (190 degrees F). Then pour over the herbs and cap tightly. Allow to stand for three to four weeks for the flavor to develop fully. Then, strain the vinegar through a damp cheesecloth or coffee filter one or more times until the vinegar is no longer cloudy. Discard the fruit, vegetable and/or herbs. Pour the strained vinegar into a clean sterilized jar. Add a sprig or two of fresh herbs or berries that have been sanitized as described above. Seal tightly. Store in the refrigerator for the freshest retention of flavors.

The flavoring process can be shortened by a week or so by bruising or coarsely chopping the herbs and fruits before placing in the bottles and adding the hot vinegar. To test for flavor development, place a few drops of the flavored vinegar on some white bread and taste. When the flavor is appropriate, strain through damp cheesecloth and continue as described above.

Storage and Use
For the best retention of flavors, store vinegars in the refrigerator or a cool dark place. If properly prepared, flavored vinegars should retain good quality for two to three months in cool room storage and for six to eight months in refrigerated storage. Some people enjoy displaying pretty bottles of herb and fruit vinegars on a kitchen window sill. If left out for more than a few weeks, these bottles are best considered as decoration and not used in food preparation. Flavored vinegars can be used in any recipe that calls for plain vinegar. They add zest to marinades for meats and fish and interesting flavors to dressings for salads, pastas and vegetables.

FLAVORED OILS
Infused oils and oil-based mixtures of garlic, herbs or dried tomatoes can pose a health hazard if not kept refrigerated. There have been a number of cases of botulism poisoning traced to commercially and home prepared mixtures of garlic-in-oil that were not refrigerated. Refrigeration is necessary because all other conditions that favor the growth of C. botulinum are met: low acid environment with pH higher that 4.6, anaerobic conditions (oil), food and moisture source (garlic), not boiled before eating. Vegetables and herbs in oil. Less has been documented on the dangers of storing whole chilies, fleshy vegetables or herbs in oil, but they, too, are best made fresh with leftovers stored in the refrigerator for use within three weeks. Vegetables have a high water activity level which further encourages the growth of C. botulinum bacteria in an anaerobic environment. Even when dried, there is still the potential for risk, unless the vegetable has been acidified to a pH of 4.6 or lower. Dried tomatoes in oil are less of a safety concern than other mixtures in oil because the pH of tomatoes is generally 4.6 or lower. In addition, by drying the tomatoes, conditions become even less favorable to growth of C. botulinum due to a decrease in water activity. Dried herbs in oil also are less of a safety concern because of their low water activity. However, to insure safety it is recommended that all tomato in oil and herb in oil products be stored at refrigerator temperatures.

Avoid Rancidity
In addition to reducing the potential for growth of C. botulinum bacteria, storing flavored oils in the refrigerator helps keep the oils from becoming rancid. A putrid “off” odor indicates the development of rancidity. All fats and oils will become rancid given enough exposure to air, sunlight and heat. Polyunsaturated fats, like vegetable oils, are especially prone to such deterioration. Eating rancid food won’t make you sick, but it may be unhealthy in the long run. Rancid fat contains chemicals called peroxides and aldehydes that can damage cells and may even encourage cholesterol to clog arteries.

It is important to note that rancidity and the presence of botulinal toxins are not necessarily related. Toxin may be present without any hint of an off-odor. Likewise, an off-odor does not necessarily indicate the presence of botulism toxin. It does, however, indicate the product may have been left for long periods at room temperature, which would promote the growth of C. botulinum. Therefore, it’s best to discard any oil-based mixtures that have become rancid so they’re out of reach of humans or animals.

Fresh Dill Vinegar
8 sprigs of fresh dill
4 cups (1 quart) white vinegar
Wash dill and dip in solution of 1 teaspoon household bleach in 6 cups water. Rinse thoroughly under cool running water. Place dill in sterilized quart jar. Heat vinegar to just below the boiling point (190 degrees F); pour over dill. Cap tightly and allow to stand in cool, dark place for three to four weeks. Strain vinegar, discarding dill. Pour vinegar into clean sterilized bottles with tight fitting covers. Add a fresh sprig of cleaned and sanitized dill, if desired. Store in the refrigerator. Makes 1 quart.

Herbal Vinegar
4 cups red wine vinegar
8 sprigs fresh parsley
2 teaspoons thyme leaves
1 teaspoon rosemary leaves
1 teaspoon sage leaves
Thoroughly wash herbs and dip in solution of 1 teaspoon household bleach in 6 cups water. Rinse thoroughly under cool running water. Place dill in sterilized quart jar. Heat vinegar to just below the boiling point (190 degrees F); pour over dill. Cap tightly and allow to stand in cool, dark place for three to four weeks. Strain vinegar, discarding dill. Pour vinegar into clean sterilized bottles with tight fitting covers. Add a fresh sprig of cleaned and sanitized parsley, if desired. Store in the refrigerator. Makes 1 quart.