Chapter 1: Integrated Pest Management (IPM)

Transcription

1 Chapter 1: Integrated Pest Management (IPM) Introduction Pests are an inevitable problem faced by nursery growers. For the purposes of this document, the term pest refers to insects, diseases, weeds, slugs, deer, and other undesirable organisms that impact our ability to grow, manage and sell ornamental plants. According to the federal Pest Control Products Act (2002), "pest" means an animal, a plant or other organism that is injurious, noxious or troublesome, whether directly or indirectly, and an injurious, noxious or troublesome condition or organic function of an animal, a plant or other organism. Pests need to be properly managed in order to mitigate their impacts on a nursery s business. Integrated Pest Management (IPM) is a scientifically based decision-making process that considers all available information and control strategies to manage these pest problems effectively, economically and in an environmentally sustainable manner. It should be noted that IPM does not preclude the use of pesticides as they are important, viable and legal pest management tools in Canada. However, when an IPM program is implemented, pesticide use is often unnecessary or is greatly reduced and only needed as a last resort. As a result IPM is not a simple concept and requires an understanding of the ecology of the crop, the behavior of the pest, the nature of the surrounding environment and of the available pest management tools. Definition There are many differing definitions for IPM all of which share the same concepts. As a general definition the British Columbia Pesticide Control Act (1997) states: Integrated pest management" means a process for managing pest populations that includes the following elements: 1

2 (a) planning and managing ecosystems to prevent organisms from becoming pests; (b) identifying pest problems and potential pest problems; (c) monitoring populations of pests and beneficial organisms, damage caused by pests and environmental conditions; (d) using injury thresholds in making treatment decisions; (e) suppressing pest populations to acceptable levels using strategies based on considerations of (i) biological, physical, cultural, mechanical, behavioural and chemical controls in appropriate combinations, and (ii) environmental and human health protection; (f) evaluating the effectiveness of pest management treatments. These six main steps can be summarized as (1) Prevention, (2) Identification, (3) Monitoring, (4) Thresholds, (5) Treatments and (6) Evaluation. Step 1: Prevention Preventing pest problems is considered to be the true foundation of IPM and is the key to successfully managing pests in the long term. The idea is to implement good horticultural practices in order to grow healthy plants in a healthy ecosystem. By doing this one can often eliminate pests entirely or greatly reduce their impact on your business. When establishing an IPM program one should always focus first on prevention. By implementing simple preventative measures or cultural controls you can avoid costlier direct control measures. Common prevention methods include: Selecting clean nursery stock (start with clean plants, buy certified plants, grow resistant varieties, varieties suitable for local climate and site, avoid monocultures or grouping plants that share similar pest problems, etc.) Site preparation (nursery layout conducive to plant health, nursery beds, nursery access, etc.) 2

3 Habitat modification (reduction of pest resources like weeds, enhancement of natural enemies, etc.) Optimizing crop growth (planting and transplanting techniques, spacing, irrigation, fertilizing, pruning, staking, media mixtures, etc.) Sanitation (waste management) Education Step 2: Identification Next to prevention, identification is probably the most important step in IPM. In order to effectively plan a pest management program, you must know if there is a pest problem in the first place and if so what pests you are dealing with. Identification not only includes the pest but also, more importantly, involves accurately identifying the affected plants. Proper identification of the plants(s) and pest(s) will make it much easier to utilize resources and find good information to plan your next moves. As you gain experience it will also be helpful to identify beneficial organisms. If these are present they may be in sufficient numbers to deal with the pest outbreaks without needing any other intervention. Beneficial organisms are the good guys and should be encouraged in the nursery. Once the plant has been identified, the pest manager will be able to look up information on the types of pests that are commonly found which will greatly assist in identification of any pest(s) present. You will then be able to find information on that pest so that you can focus monitoring efforts at the appropriate times, effectively use the appropriate treatments, know if the pest has naturally occurring enemies in the area and plan appropriate preventative measures and improve your pest management practices. Plants, pests and beneficial organisms may be identified by: Comparing to specimens in insect, weed or herbarium collections Referring to reference books, internet resources and fact sheets Consulting experts for help Comparing damage characteristics (symptoms and signs) with published images 3

4 Step 3: Monitoring Regularly inspecting your plants for the presence of pests and recording what you see will help to determine whether treatments will be needed or not. By keeping these records for many years you will gain a better understanding of when certain pests will become problems in your nursery. Monitoring is used to: Detect problems while pest numbers are still low Assess the size and spread of a pest population and extent of damage Find out if natural enemies of pests are present and in what numbers Look for conditions that contribute to the pest problem Find out what effect treatments or natural enemies have had on the pest population Step 4: Thresholds Based on your monitoring data you can determine the best time to implement pest control treatments. Just because you see a pest organism on your plants is not a reason to spray a pesticide, particularly if there is no evidence of damage caused by the pest. This is simply an opportunity to continue your monitoring program and look for presence of beneficial organisms. At some point, however, the pest population will be high enough that you will begin to expect visible damage and potential losses. This will be the point at which you apply your treatments so that economic losses do not result. This point is called your action threshold. If you wait too long, you will begin to see an unacceptable amount of injury of damage, called the injury threshold. Maintaining monitoring records is an important tool in establishing your action thresholds. Often it takes a number of seasons to refine the point at which you will make your treatments. You may be surprised to see on many occasions that the pests may actually disappear naturally without the need to implement controls! 4

5 Step 5: Treatments In an IPM program, one must consider all available control measures and select the most appropriate ones when dealing with pest outbreaks. There are many different types of pest control treatments. Cultural Control (prevention, sanitation) Physical Control (manual techniques: pruning, hand pulling weeds, barriers, traps) Mechanical Control (machines or devices: vacuums, animal repellers) Biological Control (natural enemies: beneficial insects, mites and pathogens) Chemical Control (any product with a Canadian pest control products number: conventional pesticides, horticultural oils, soap, etc.) If you are implementing routine and effective preventative measures often you will not need to resort to other treatment options. Step 6: Evaluation Since IPM is a dynamic process, routine evaluation of the program is essential because it helps to determine what worked and what did not. This is why good record keeping is important. The program can then be modified in subsequent seasons to be even more effective. 5