Spokane County Extension

Agriculture and Natural Resources

INTEGRATED PEST MANAGEMENT

What is IPM?
There are several definitions of integrated pest management (IPM), but they all include the following points.   

• Every environment or micro-environment, such as a cropping system on a farm, is a component of a larger ecosystem.  The goal of IPM is to restore balances in the system, not to eliminate species.  Monitoring makes it possible to evaluate the populations of pest and beneficial organisms, and to avoid or limit the disruption of natural controls of both the target pest and other potential pests

 • The presence of a pest does not necessarily mean that the cost of the damage is greater than the cost of the control. Determine whether this economic threshold has been reached before controlling the problem.

  • IPM usually combines several management techniques, so it is important that one technique does not conflict with another.

Two IPM Definitions

IPM is a sustainable approach to managing pests by combining biological, cultural, physical, and chemical tools in a way that minimizes economic, health, and environmental risks. — National Coalition on IPM, January 1994 

Systems such as IPM are based on extensive collection and interpretation of field-level data to determine pest infestation thresholds, protect non-target and beneficial species, utilize predators and parasites, and rely on synthetic pesticide use only as a last resort. — Rick Rominger, 1993.  California Farmer, USDA Deputy - Secretary

Why use IPM?

A farm is a dynamic biological and socioeconomic system.  Factors that influence a farm include soil fertility, weather, crop prices, neighboring farm activities, government regulations,  and interest rates.  Population growth, accompanied by higher living standards, increases demands on natural resources. Consequently, sustainable management of these limited resources is important.  Farmers and ranchers will be required to manage their land with reduced impact  on water and other resources.  More governmental regulation of pesticides is likely and pest management must reflect these changes.

The public is particularly concerned with environmental quality and food safety.  These concerns will probably drive legislation that restricts the use of synthetic agrochemicals.  IPM typically uses less agrochemicals than does conventional pest management. 

IPM Strategies

Monitoring
Monitoring involves systematically checking the fields for pests at regular intervals and at critical times to gather information about the crop, pests, and natural enemies.  Sweep nets, sticky traps, and pheromone traps can be used to collect insects for both identification and population density information.  Leaf counts are one method for recording plant growth stages.  Square-foot or larger grids laid out in a field can provide a basis for comparative weed counts.  Records of rainfall and temperature are sometimes used to predict the likelihood of disease infections.

Specific scouting methods have been developed for many crops. The Cooperative Extension System can provide a list of IPM manuals available.  Many resources are now available via Internet.

The more often a crop is monitored, the more information you have about what is happening in the fields.  Monitoring activity should be balanced against its costs.  Frequency may vary with temperature, crop, growth phase of the crop, and pest populations.  If a pest population is approaching economically damaging levels, monitor more often to keep a close eye on population increases or decreases.

Pest Identification
The first and most important step is to identify the pest.  The effectiveness of subsequent pest management depends on correct identification.  Misidentification of the pest may be worse than useless; it may actually be harmful and cost time and money.  Help with positive identification of pests may be obtained from university personnel, private consultants, Cooperative Extension, and books listed in Useful Resources.

Evaluation
After a pest is identified, scout fields periodically, and also determine economic injury and action levels for the pest. Also consider the following questions when choosing appropriate and effective management tools.

          What are host and non-host crops of this pest?
         
When does the pest emerge or first appear?
         
Where does it lay its eggs? 
         
In the case of weeds, where is the seed source?
         
Where, how, and in what form does the pest overwinter?
         
Can the cropping system be altered to make life more difficult for the pest and easier for its natural controls?

IPM Control methods
There are four general methods to manage insect, disease, and weed problems.  These are cultural, biological, mechanical, and chemical.  Several of these tactics may be carried on concurrently or implemented at different times to achieve a truly integrated approach.

Cultural Control
Cultural control is the manipulation of the environment to avoid serious pest damage.  It depends on knowledge of both the plant’s needs and its potential problems.  Cultural practices include: site selection and preparation, sanitation, pest free planting stock, crop rotation, trap cropping, timing of planting or harvest, maintaining a healthy crop, and habitat manipulation.  For example, most plants have an ideal site in which they will flourish.  In a poor site, they become stressed and prone to greater pest attack.

Biological Control
Biological control is the use of living organisms, either native or introduced, to suppress pests below levels of serious economic or aesthetic damage.  There are three general strategies employed in biological control:

Conservation; protecting and enhancing the biological control agents that are already present. 
Augmentation adds to the established base of beneficials or restores a decimated population. 
Introduction involves the introduction of beneficials into a new area..

Mechanical Control
This is probably the oldest form of pest control. It includes hand weeding, picking pests off crops, cultivating, mowing and physical barriers.

Chemical Control
Pesticides continue to be important in IPM.  IPM stresses the consideration of less disruptive methods, but where pesticides are appropriate, they should be used on an as needed rather than on a calendar basis.  Select the most appropriate material based on several criteria including: potential for groundwater contamination, toxicity to mammals, effectiveness, disruption to natural enemies, and resistance management. 

Record-keeping
Monitoring goes hand in hand with record keeping, which form the collective "memory" of the farm.  Records should not only provide information about when and where pest problems have occurred, but should also incorporate information about cultural practices (irrigation, cultivation, fertilization, mowing, etc.) and their effect on pest and beneficial populations.  The effect of non-biotic factors, especially weather, on pest and beneficial populations should also be noted.  Record keeping forms the basis for future pest management decisions.   A variety of software programs are now available to help growers keep track of — and access — information about inputs and outputs of their farm.

Economic injury and action levels
The economic injury level (EIL) is the pest population that inflicts crop damage greater than the cost of control measures.  Careful monitoring of the pest is necessary if you want to act before a population reaches its EIL. EIL's are directly related to the value of the crop, the stage of crop development, and the part of the crop being attacked.  For example, a pest that attacks the fruit or vegetable will have a much lower EIL (that is, it must be controlled at  lower levels) than a pest that attacks a non-edible part of the plant.  The exception to this rule is an insect or nematode pest that is also a disease vector.  

The benefits of IPM may include:

·         Reduced input costs

·         Reduced on-farm and off-farm environmental impacts

·         More effective pest management

·         IPM strategies may help to prevent pest problems from developing, and may also reduce or eliminate the use of chemicals in managing problems that do arise. 

Special Considerations

Cosmetic damage and aesthetics
Consumer attitude towards produce appearance is often a major factor when determining a crop's sale price.  Cosmetic damage is an important factor when calculating the EIL, since pest damage, however superficial, lowers a crop's market value.  Growers selling to markets that are informed about IPM or about organically grown produce may be able to tolerate higher levels of cosmetic damage to their produce.

Time and resources
A successful IPM program takes time, money, patience, short- and long-term planning, flexibility, and commitment. The pest manager must spend time on self-education and on making contacts with Extension and research personnel to discuss his or her farming operation.  This will aid in developing an integrated plan for the farm. In addition, certain IPM strategies, such as increasing beneficial insect habitat, may take more than a year to show results.

A closely monitored IPM system may require a larger initial outlay in terms of time and money than a conventional chemical spray program.  In the long run, however, a good IPM program should pay for itself.  Direct pesticide application costs are saved and equipment wear and tear may be reduced.  

 More reasons to reduce pesticide use through IPM

Resistance: Pesticide use is a powerful selection pressure for changing the genetic make-up of a pest population.  Naturally resistant individuals in a pest population are able to survive pesticide treatments.  The survivors pass on the resistance trait to their offspring.  The result is a much higher percentage of the pest population resistant to a pesticide.  In the last decade, the number of weed species known to be resistant to herbicides rose from 48 to 270, and the number of plant pathogens resistant to fungicides grew from 100 to 150.  Resistance to insecticides is so common — more than 500 species — that nobody is really keeping score .  

Resurgence: Pesticides often kill off natural enemies along with the pest.  With their natural enemies eliminated, there is little to prevent recovered pest populations from exploding to higher, more damaging numbers than existed before pesticides were applied.  Additional chemical pesticide treatments only repeat this cycle.  

Secondary Pests: Some potential pests that are normally kept under control by natural enemies become actual pests after pesticides destroy their natural enemies.  Mite outbreaks after pesticide applications are a classic example of this.  

Residues: Only a minute portion of any pesticide application will contact the target organism.  The remainder may degrade harmlessly; but too often water, wind and soil will carry pesticides to non-target areas and organisms, affecting the health of human and wildlife populations.

SUMMARY
With the advent of new technologies and regulations, agriculture is undergoing increasingly rapid change.  IPM is advancing just as quickly for the same reasons.

IPM can be a flexible and valuable tool when used as a concept with which to approach pest management.  IPM is not a cookbook recipe for pest control, but a flexible approach for dealing with agriculture's ever-changing financial and physical environment.

The key to effective IPM is the farmer's understanding of its concepts.

Compiled by Don Dysart . For information call WSU Extension, (509)
477-2048.

Sources

Integrated Pest Management
Fundamentals of Sustainable Agriculture 

Appropriate Technology Transfer for Rural Areas (ATTRA)
P.O. Box 3657
Fayetteville, AR 72702
Phone: 1-800-346-9140 --- FAX: (501) 442-9842

Back

 

Secondary content using h2 tag. Column 2

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Heading using the h3tag

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Spokane County Extension, 222 N Havana, Spokane WA 99202-4799, 509-477-2048, Contact Us