Pest Control

It refers to the regulation or management of a species defined as a pest, and can be perceived to be detrimental to a person’s health, the ecology or the economy. A practitioner of pest control is called an exterminator. Pest control is at least as old as agriculture, as there has always been a need to keep crops free from pests. In order to maximize food production, it is advantageous to protect crops from competing species of plants, as well as from herbivores competing with humans.

A pest can be any insect, rodent, fungus, or weed as well as other organisms, which is unwanted. Urban pests can be generally characterized as organisms (excluding parasitic microorganisms) which have human health or aesthetic implications, or which damage wooden support structures of buildings.

Types of pests include:

• insects, such as roaches, termites. mosquitoes. aphids. beetles, fleas. and caterpillars,
• insect-like organisms, such as mites. ticks, and spiders,
• microbial organisms. such as bacteria. fungi, nematodes, viruses, and mycoplasmas,
• which are any plants growing where they are not wanted.
• such as snails, slugs, and shipworms, and
• vertebrates, such as rats. mice, other rodents. birds. fish, and snakes.

Most organisms are not pests. A species may be a pest in some situations and not in others

Categories of pests include:

• continuous pests that are nearly always present and require regular control.
• sporadic, migratory. or cyclical pests that require control occasionally or intermittently.
• a potential pests that do not require control under normal conditions, but may require control in certain circumstances.

Many pests have only become a problem as a result of the direct actions by humans. Modifying these actions can often substantially reduce the pest problem. House flies tend to accumulate wherever there is human activity and live in close association with people all over the world especially where food or food waste is exposed. Similarly, seagulls have become pests at many seaside resorts. Tourists would often feed the birds with scraps of fish and chips, and before long, the birds would rely on this food source and act aggressively towards humans.

Living organisms evolve and increase their resistance to biological, chemical, physical or any other form of control. Unless the target population is completely exterminated or is rendered incapable of reproduction, the surviving population will inevitably acquire a tolerance of whatever pressures are brought to bear

Types of pest control

• Use of pest-destroying animals – Perhaps as far ago as 3000BC in Egypt, cats were being used to control pests of grain stores such as rodents.
• Biological pest control – Biological pest control is the control of one through the control and management of natural predators and parasites. For example: mosquitoes are often controlled by putting Bt Bacillus thuringiensis ssp. israelensis, a bacterium that infects and kills mosquito larvae, in local water sources. The treatment has no known negative consequences on the remaining ecology and is safe for humans to drink. The point of biological pest control, or any natural pest control, is to eliminate a pest with minimal harm to the ecological balance of the environment in its present form.
• Mechanical pest control – Mechanical pest control is the use of hands-on techniques as well as simple equipment and devices, that provides a protective barrier between plants and insects. For example: weeds can be controlled by being physically removed from the ground. This is referred to as tillage and is one of the oldest methods of weed control.
• Physical pest control – Physical pest control is a method of getting rid of insects and small rodents by removing, attacking, setting up barriers that will prevent further destruction of one’s plants, or forcing insect infestations to become visual.
• Elimination of breeding grounds – Proper waste management and drainage of still water, eliminates the breeding ground of many pests.Garbage provides food and shelter for many unwanted organisms, as well as an area where still water might collect and be used as a breeding ground by mosquitoes. Communities that have proper garbage collection and disposal, have far less of a problem with rats, cockroaches, mosquitoes, flies and other pests than those that don’t. Open air sewers are ample breeding ground for various pests as well. By building and maintaining a proper sewer system, this problem is eliminated.
• Poisoned bait – Poisoned bait is a common method for controlling rat populations, however is not as effective when there are other food sources around, such as garbage. Poisoned meats have been used for centuries for killing off wolves, birds that were seen to threaten crops, and against other creatures. This can be a problem, since a carcass which has been poisoned will kill not only the targeted animal, but also every other animal which feeds on the carcass. Humans have also been killed by coming in contact with poisoned meat, or by eating an animal which had fed on a poisoned carcass. This tool is also used to manage several caterpillars e.g. Spodoptera litura, fruit flies, snails and slugs, crabs etc.
• Trap Cropping – A trap crop is a plant that attracts pests, diverting them from other crops in an agricultural field. This leads to pest aggregation on the trap crop, where they can be more easily and cost effectively controlled using pesticides or control methods. However, trap-cropping, on its own, has often failed to cost effectively reduce pest densities on large commercial scales, without the use of pesticides, possibly due to the pests ability to disperse back into the main field.
• Traps – Unlike trap crops, most traps used to control pests are manmade. A variety of mouse traps and rat traps are available for mice and rats, including snap traps, glue traps and live catch traps. Sticky traps, which often include pheromones to attract the pest, are also a common way of controlling many moth pests, such as Indian mealmoths.
• Pesticides – Spraying pesticides by planes, trucks or by hand is a common method of pest control. Crop dusters commonly fly over farmland and spray pesticides to kill off pests that would threaten the crops. However, some pesticides may cause cancer and other health problems, as well as harming wildlife.
• Inspection – Pests do not infest uniformly; they focus on specific areas. These sites must be located. Training and experience in conducting inspections are important for successful location of infested areas.
• Habitat Alteration – Since infested areas provide harborage for pests (one of the elements along with food and water needed by pests to thrive), changing or eliminating some of these favorable elements will make survival less successful. Such changes commonly include increased sanitation, moisture reduction, and the elimination of clutter.
• Natural Control – Some natural forces act on all organisms. causing the populations to rise and fall. These natural forces act independently of humans and may either help or hinder pest control. Natural forces that affect pest populations include climate, natural enemies, natural barriers availability of shelter, food and water supplies.

Styles of pest control

In the urban setting, current industrial or structural pest control activities can be characterized in four styles: prevention, reaction, extermination, and integrated pest management.

• Preventive Pest Control – In preventive control, a technician follows a pre-established schedule, or route. While the inspection can indicate where pests occur, with this style, pesticides are usually applied regardless of whether pests are observed or not. Those who practice this style are satisfied that pests will be killed as they contact the pesticide residue.
• Reactive Pest Control – In reactive pest control, a technician responds to special, unscheduled calls.
• Pest Elimination or Pest Extermination – A senior technician, usually a supervisor, responds to an appointment.

Accurate identification is the first step in an effective pest management program. Control a pest only when it is causing or is expected to cause more harm than is reasonable to accept. Use a control strategy that will reduce the pest numbers to an acceptable level. Cause as little harm as possible to everything except the pest. In most pest control situations, the area to be protected should be monitored (checked or scouted) often. Whenever you try to control a pest, you will want to achieve one of these three goals. or some combination of them

• prevention – keeping a pest from becoming a problem.
• suppression – reducing pest numbers or damage to an acceptable level. and
• eradication – destroying an entire pest population.

Integrated Pest Management

Integrated pest management is the combining of appropriate pest control tactics into a single plan (strategy) to reduce pests and their damage to an acceptable level. Using many different tactics to control a pest problem tends to cause the least disruption to the living organisms and nonliving surroundings at the treatment site. Rely only on pesticides for pest control can cause pests to develop resistance for pesticides, can cause outbreaks of other pests and can harm surfaces or non-target organisms. With some types of pests. use of pesticides as the only tactic will achieve very poor control. To solve pest problems, you must:

• identify the pest or pests and determine whether control is warranted for each.
• determine your pest control goal
• know what control lactics are available.
• evaluate the benefits and risks of each tactic or combination of tactics.
• choose a strategy that will be most effective and will cause the least harm 10 people and the environment.
• use each tactic in the strategy correctly,

The strategy you choose will depend on the pest you have identified and the kind and amount of control you need.

Pest management equipment

The most needed and reliable tool of all in pest management is the brain and ability of a technician to use his knowledge of pest management along with well-cared-for equipment and good supplies. Pesticide application equipment used in urban pest management is, for the most part, time tested and reliable.

Failure to care for equipment properly can cause serious problems. Using worn or clogged spray nozzles or caked dusters results in misapplied pesticides. Accidents from breaking hoses and exposure from leaking valves can result in lost time and illness.

The more commonly used equipment includes

• Hand held compressed air sprayers – The small (one or two litre) stainless steel spray
• tank is used to apply a flushing agent, or a residual pesticide. Depending on the nozzle selection, it applies different spray patterns; and depending on the amount of pumping, it delivers the pesticide under high or low pressure.
• Power sprayers use electric or gasoline engines to pump liquid insecticides from a relatively large tank, usually over 100 litres.
• Canned insecticides – Canned aerosol pesticides consist of a pressurized fluid that produce an aerosol or fog droplet that floats in the air for a period of time, then settles to the ground. The droplet size is governed by the nozzle and valve at the top of the can.
• Aerosol and fog generators
• Dusters
• Bait Stations
• Traps, monitoring devices etc.

Insecticide

An insecticide is a substance used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively.

The Insecticides Act, 1968 and Insecticides Rules, 1971 regulate the import, registration process, manufacture, sale, transport, distribution and use of insecticides (pesticides) with a view to prevent risk to human beings or animals and for all connected matters, throughout India. All insecticides (pesticides) have to necessarily undergo the registration process with the Central Insecticides Board & Registration Committee (CIB & RC) before they can be made available for use or sale.

Thus, technically all insecticides (pesticides) in India are those substances that are listed on the “Schedule” of the Insecticides Act, 1968. The Registration Certificate mandates that a label be put on the packaging, which clearly indicates the nature of the insecticide (Agricultural or Household use), composition, active ingredient, target pest(s), recommended dosage, caution sign and safety precautions. Therefore, a pesticide labeled for agriculture should not be used in a household.

Insecticide-based pest control products are composed of a mixture of chemicals classified as either “active ingredients” or “inert ingredients.” The specific chemical(s) in the mixture responsible for affecting the pest organism is referred to as the active ingredient. Most commonly, the active ingredient is formulated with other chemicals, called inert ingredients. While inert ingredients enhance product efficacy and make end-use products easier to use and safer to handle, they have little toxicity toward target pests.

An active ingredient’s chemical name is based on a strict set of internationally adopted rules of nomenclature established by the International Union of Pure and Applied Chemistry (IUPAC) or the CAS (Chemical Abstracts Systematic name). These rules are considered the language of chemistry. Embedded within every chemical name are pieces of information that describe the exact arrangement of every atom and chemical bond in the molecule. Active ingredients are also known by their common name.

(1) is the name given to it by the manufacturer. The common name (2) of the product’s active ingredient (2) is also known by its chemical name (3).

Other terms related to insecticide labeling, are

• Active ingredient. The chemical substance(s) responsible for achieving a product’s desired effect.
• Technical grade active ingredient. The chemical substance(s) (pesticide) in its pure, raw form (usually 95% to 100% active ingredient) prior to being formulated into a product.
• Inert ingredient. Inert ingredients are biologically inactive chemicals (i.e., they typically have no pesticidal properties) that are mixed with active ingredients to produce an end-use, for-sale product. Some commonly used types of inert ingredients and their functions include:
  • Emulsifiers allow petroleum-soluble (but water insoluble) active ingredients to evenly disperse in water.
  • Diluents and carriers are meant to dilute the amount of active ingredient in a formulation and to carry it to its intended target. Often the same material serves as
  • both diluent and carrier. For example, talc is an inert ingredient in many dust formulations. Only a small part of the dust formulation is insecticidal. The remainder is inert talc that not only dilutes the active ingredient but also carries it to its intended target. In liquid spray formulations, water is both a diluent and carrier. In granular formulations, the inert granule on which the pesticide is absorbed is the carrier.
  • Stickers allow active ingredients to stick or adhere to the treated surface.
  • Wetting agents (e.g., spreaders, dispersants, penetrants) are inert chemicals that are added to water to increase spreading and/or penetration by eliminating or reducing surface tension.
• Solutions are liquids and all the chemicals that are dissolved in the liquid. For example, sugar or salt dissolve completely when placed in water to make a “sugar solution” or “salt solution.”
• A suspension is a liquid that contains solid particles that are not dissolved. Over time, the solid particles will settle to the bottom of the container. Many liquid spray formulations (wettable powders, suspendable concentrates, and microencapsulates) are suspensions in water, and will settle to the bottom of the sprayer if not agitated. Suspensions should be shaken, or agitated, often to resuspend the product in the water.
• Contact toxicants are chemicals that penetrate the target organism on contact. For example, liquid sprays are usually effective only after an insect crawls on the treated surface and contacts the residual deposit.
• Oral toxicants are chemicals that act after having been ingested by the target organism. For example, bait products kill only after an insect consumes the bait containing the active ingredient.
• Fumigants are chemical gasses. They act after an insect breathes them.

Classification of the   Insecticides	Medium lethal dose by   the oral route acute toxicity LD 50 mg/ kg.. body weight of test animals	Medium lethal dose by the dermal route dermal toxicity LD 50 mg/kg. Body weight of test animals	Colour of identification band on the label
1. Extremely toxic	1-50	1-200	Bright red
2. Highly toxic	51-500	201-2000	Bright yellow
3. Moderately toxic	501-5000	2001-20000	Bright blue
4. Slightly toxic	More than 5000	More than 20000	Bright green