Please note that pesticide and biocontrol recommendations differ from state to state or between countries. The information presented should be used as a guideline for pest management but should not take the place of the official word of your local county agent or regulatory official.
Pest management is an integral part of any greenhouse operation. Pests can include weeds, nematodes, algae, insects, spiders, diseases, or any unwanted organism that directly or indirectly damages plants. Many greenhouses use Integrated Pest Management (IPM) strategies to manage their pest problems.
IPM can be defined as a systematic approach to managing pests that focuses on long-term prevention or suppression with minimal impact on human health, the environment, and non-target organisms.
An IPM Program consists of:
Many growers use IPM in the management of their greenhouses on an ongoing basis. This module will introduce you to Cornell's approach to IPM. Other examples include:
I. Basics of Integrated Pest Management
Threshold tolerance determines the point at which damage and reduced yield will occur if no action is taken. Growers have thresholds that they have learned through experience or from scientific research. The greenhouse grower must determine how much damage can be tolerated before taking action. The decision made must take into account effects on the environment.
1. Monitoring (Scouting) and Assessing
2. Identification of Pest Problems
1. Insects and spiders
A very brief summary of diseases is presented here, but for more detailed information on plant pathogens go to Cornell University's On-Line Glossary of Technical Terms in Plant Pathology.
3. Environmental Conditions
A summary of environmental conditions and the symptoms they produce is a useful tool in the greenhouse.
4.Weeds
5.Nematodes
6. Algae
7. Slugs and Snails
3. Control Methods
Once a greenhouse has been properly scouted and assessed, and pests identified, appropriate action should be taken. This can be biological, chemical, cultural, mechanical, or a combination of these strategies.
Biological control (Biocontrol) refers to the use of biological agents (plant, animal, or microbe) to control pests and is a key strategy in a well-managed IPM program.
Biological control includes what the EPA defines as biopesticides, resistant plant varieties, and beneficial organisms. Biological control is safer than conventional chemical control because it allows the greenhouse grower to eliminate or minimize spraying. IPM stesses the use of pest management strategies that have the least impact on the environment.~Biopesticides
- EPA Office of Pesticides Program list of biocontrols (biopesticides)
~Resistant Plant Varieties~Beneficial Organisms
- fungus
- bacteria
To learn how the greenhouse manager can raise beneficial predators for the control of pests, see Hungry, Helpful Insects Thrive on Special Fast-Food. For more information on biological controls and predatory organisms go to Additional Resources. Remember! Biological controls are living creatures and can be adversely affected by chemical use and certain environmental conditions.
The EPA classifies pesticides into two categories:
~General Use
General use pesticides are relatively safe, can be used in home greenhouses and can be purchased from a garden center, a hardware store, supermarket, etc. No special certification or licensing is required.~Restricted Use
A Restricted Use classification restricts a product, or its uses, to application by a certified pesticide applicator or under the direct supervision of a certified applicator.There is a great deal more information you need to know to apply restricted pesticides that are not covered in this beginner's course but would be covered in a Pesticide Certification Training course.
Cultural pest management places a focus on proper environmental conditions and the care critical to maintaining them. It includes such things as proper watering, fertilizing, potting , and pest management techniques. The goal of cultural pest management is the creation and maintenance of a well-organized, sanitized greenhouse.
Mechanical control refers to hands-on and exclusion techniques. With hands-on techniques the greenhouse manager becomes the tool when handpicking and destroying insect pests.
Exclusion techniques include ways to exclude or keep pests out of the greenhouse; such as making sure doors are closed, non-essential people and "pet plants" are kept out of designated areas, and through the introduction of barriers (screens).
4. Evaluation
Evaluation includes keeping records of all aspects of the IPM program the manager followed including techniques used, pests identified, and so on. These records are valuable to future management decisions.
John Kumpf on Integrated Pest Control—
"Pest management in the greenhouse often means getting down on your hands and knees to pull weeds or check for bugs. This approach will reduce herbicide use in the greenhouse."
The most important tool for the safe and efficient use of pesticides is the information contained on the product label. Failure to follow the directions on the pesticide label can harm people and the environment and can result in possible liabilities. Labels are legal documents and contain the following:
Worker Protection Standard Guidelines is a set of regulations developed by the EPA for the protection of workers from agricultural pesticides. Both general-use and restricted-use pesticides are covered by the WPS.
Workers must be warned prior to application. Dependent upon the pesticide used, this notification can be oral, written or both. The following is a list of important pesticide-related signs to become familiar with:
The law requires that the employer notify workers of any pesticide application in the greenhouse.
If the pesticide product labeling has a statement requiring both the posting of treated areas and oral notification to workers, the employer shall also provide oral notification of the application to the worker in a manner that the worker can understand. The warning shall consist of:
Greenhouses are structures enclosed with a nonporous covering. This makes ventilation an important consideration when spraying pesticides.
The EPA has established regulations for greenhouse spraying that require that ventilation continue until the air concentration is measured to be equal to or less than the inhalation exposure level that the labeling requires to be achieved.
If no inhalation exposure level is listed on the labeling, ventilation shall continue until after one of the following requirements has been met.
CAUTION! Pesticide or biocontrol recommendations made on any of the links from this page may not be legal in your state or country. Please check with your local county agent or regulatory official before using any pesticide or biocontrol mentioned on any of the links from this page.