- Ornamental Pest Management
Training for Commercial Pesticide Applicators
Category 3B
- Principles of Pest Management
Chapter1
- A pesticide applicator is not merely a person who applies pesticides. Social and legal responsibility accompanies the use of these chemical tools.
- Properly applied pesticides are more likely to protect plant material from pest injury and less likely to endanger nontarget organisms. To achieve this, you must consider the entire system including the pest, its environment, and the impact of other management activities performed.
- In other words, you must use Integrated Pest Management.
- As defined in the core manual, IPM is the use of all available strategies to manage pests so that an acceptable yield and quality can be achieved economically with the least disruption to the environment.
- Pest control strategies used in ornamental plant IPM include:
-Resistant plant varieties
-Cultural practices
-Natural enemies and
-Mechanical controls
-Pesticides.
IPM incorporates pesticides at the most appropriate time for pest control and only when necessary.
- IPM was developed as a strategy to lengthen the effective life of pesticides and stave off resistance and has its roots in agriculture. IPM was somewhat a result of what the experience with widespread pesticide overuse and misuse in the 1960’s taught us, including:
-No one method of pest control achieves long-term pest management.
-Pest management is just one component of plant care.
-IPM often reduces pest management costs by reducing unnecessary pesticide applications.
-IPM minimizes pesticide failures due to pest resistance and destruction of natural enemies.
-Use of nonchemical controls means pest management is less threatening to nontarget organisms, including humans.
- Integrated Pest Management is a systematic approach to pest management that can be broken into five steps. Each step is a necessary part of IPM for landscape ornamental plants. They include:
-Detection of agents injuring plants by monitoring (scouting) plants regularly.
-Identification of agents injuring plants.
-Determining Economic significance
-Selection of management methods
-Evaluation of methods and results including recordkeeping.
- Early detection, before pest population reach damaging levels, is vital to successful IPM. Plant manager gain several benefits by regularly monitoring their system:
-Determine which pest specie(s) are present.
-Determine which life cycle stage of he pest is present.
-Detect low-level pest populations before significant injury has occurred.
-A variety of management techniques may be employed to maintain pest populations at low density.
-Less toxic methods may be options for controlling low-level, rather than outbreak pest populations.
- Monitoring the landscape for information used in pest management decision includes:
-Scouting is the observation of pests and/or their damage. Pests hidden from view can be uncovered, knocked of, or pulled off of foliage with a your hands or a sweep net.
-Traps are for monitoring mobile pest or those with very low density
-Weather. The rate of plant development and pest activity directly depends upon weather conditions. Note that dates on a calendar do not accurately reflect weather or pest development.
- –Phenology. Plant phenology, the relationship between weather and development progress in plants, is a reliable cue to the onset of pest activity. References like Coincide: The Orton System of Pest Management, help match the onset of pest activity with plant developmental events such a budbreak or flowering. Remember that there will be variances between locations.
-Degree Days. Plant managers should monitor weather, but pest development is most precisely measured by degree days. One degree day is a 24-hour period of accumulated time in which the temperature was above a base level. The base temperature correlates with the onset of pest activity. Base temperatures are usually 50 or 40 degrees F.
- The Crop Advisory Team of MSU publishes the CAT Alert Newsletter on a weekly basis during the growing season. The Landscape Edition is pertinent to our industry including Christmas tree production. The Alerts include degree days, pest activity and appropriate cultural practices timely for Michigan conditions. This information is also available on the World Wide Web at: http://www.msue.msu.edu/ipm/
- Include information such as: pest life stage, type and level of damage, specific host plant on data sheets designed for recording information generated from monitoring activities.
- An organism should not be considered a pest until it is identified as one. MOST organisms are not pests! To recognize plant disorders and identify the cause, you must be familiar with the healthy plant, and with agents damaging plants.
Know the healthy plant:
-What is the normal growth habit, appearance of foliage, roots, bark?
-Know natural plant processes like bark shedding, needle drop and pollen release.
Know what is damaging plants:
-Cultural, environmental problems.
-Weeds.
-Diseases.
-Insects and mites.
-Animals.
- Teasing out which of many agents is responsible for plant injury can be a big job. Using a checklist will help you to remember to investigate the whole plant as well as its environment and history.
- Have tools with you to investigate soil, roots, wood and foliage. These include pruners, soil probe, trowel, binoculars, 10x hand lens, and specimen bags. When in doubt, consult reference books, diagnostic labs, Extension bulletins and agents, and fellow diagnosticians. Remember, it is common for a plant to suffer from more than one disorder at a time.
- Landscape plant managers know that some pests threaten the health of plants, while others diminish the beauty or function of plants. At what level of injury should pests be controlled? When costs are justified by an equal or greater benefit gained form the management tactics.
Economic Significance
-The economic injury level is the density of pests at which the cost to manage the pest is equal to the losses the pest causes. Here cost refers to losses in cash crops, or death of landscape plants.
-When losses are not in terms of dollars, but rather cosmetic, the pest density resulting in unacceptable damage is called the landscape injury level. What is considered unacceptable damage is largely the opinion of the homeowner or plant manager.
-The action threshold is the pest density at which measures must be taken to prevent the pest from reaching the economic or landscape injury level.
- Note that action thresholds do not apply to nursery stock ready for sale. All plants for sale must be certified free from injurious insects and diseases.
- Plant managers must define the injury level for each pest situation in the landscape. Keep in mind that there are two ways in which pests injure ornamental plants:
-Damage to plant health. The pest outright kills the plant, or permanently weakens the plant lessening its ornamental value. Serious pests such as Dutch elm disease, chestnut blight, and bronze birch borer typically bring trees to death or near it.
-Damage to plant appearance. Most landscape pest injury is not life-threatening, but rather detracts from the aesthetic value of the plant. Pests like box elder bugs, Eastern tent caterpillar, and sooty mold are mostly nuisance pests. Note: this type of pest, at high density or if attacking already-stressed plants, may cause serious physical injury.
- The landscape injury level is a subjective assessment based on the potential for serious injury and the landscape value of the plant.
When setting landscape injury levels – Consider:
-Client’s tolerance of pest damage. Help the client distinguish between aesthetic and health-threatening injury. IPM cannot succeed when tolerances are unreasonably low.
-Landscape importance of host plant. Plants that are highly ornamental, nole, historic, or are otherwise the focal point of the landscape will have relatively low injury levels.
-Pest’s ability to reproduce and spread determines how rapidly a serious pest infestation ca occur. Pests with a great rate of reproduction or are easily spread from plant to plant will have a relatively lower action threshold.
- Personal and peer experience, and references will help you set landscape injury thresholds. Remember, setting landscape injury levels which reflect specific pest, host and weather conditions is the cornerstone of IPM.
- Many factors limit pest populations below landscape threshold levels including weather, natural enemies, and plant defenses. When pest are not sufficiently limited by natural-occurring factors, action must be taken by the plant manager. A combination of pest control methods is typically of a successful landscape pest management program.
- When choosing pest management tactics, select those that
-are least toxic to nontarget organisms.
-enhance natural controls.
-most likely to permanently limit the pest.
-are least hazardous for the applicator to handle.
-are most likely to remain on the target area.
- You also need to consider logistical limitations to your pest management activites for your IPM program to be effective and practical to implement. Factors that limit your choice of options include:
-Budget
-Availability of equipment
-Availability of labor
-Time
-Availability of products
-Public/client acceptance of methods
- A frequently overlooked, but essential part for successful IPM is evalustion of management tactics. Several questions are answered through evaluation: