EPM

(Ecological Pest Management)

What is Ecological Pest Management?

Ecological Pest Management (EPM) is also called biointensive IPM.  EPM originated from Integrated Pest Management (IPM) and shares many of the same components as conventional IPM, including monitoring, use of economic thresholds, record keeping, and planning.  An important difference between conventional and biointensive IPM, however, is that the emphasis of the latter is on proactive measures to redesign the agricultural ecosystem to the disadvantage of a pest and to the advantage of its parasite and predator complex (ATTRA).

Pest management is an ecological matter. The size of a pest population and the damage it inflicts is, to a great extent, a reflection of the design and management of a particular agricultural ecosystem.  The design and management of our agricultural systems need re-examining. We’ve come to accept routine use of biological poisons in our food systems as normal.  Attempting to implement an ecology-based discipline like IPM in large monocultures, which substitute chemical inputs for ecological design, can be an exercise in futility and inefficiency (ATTRA).

According to ATTRA, IPM, as it was originally conceived, proposed to manage pests though an understanding of their interactions with other organisms and the environment.  However, IPM has strayed from its ecological

roots. Critics of what might be termed “conventional” IPM note that it has been implemented as Integrated Pesticide Management (or even Improved Pesticide Marketing) with an emphasis on using pesticides as a tool of first resort. What has been missing from this approach, which is essentially reactive, is an understanding of the ecological basis of pest infestations. Also missing from the conventional approach are guidelines for ecology-based manipulations of the farm agroecosystem that address the questions:

Ø  Why is the pest there?

Ø  How did it arrive?

Ø  Why doesn’t the parasite/predator complex control the pest?

Guidelines for ecology-based manipulations of the farm agroecosystem:

For more information on biointensive integrated pest management strategies visit the National Sustainable Agriculture Information website and click on:

https://attra.ncat.org/attra-pub/summaries/summary.php?pub=146

Dr. Mcbug’s website (see information below) is a very good resource for EPM. 

Another good resource is:  Farmscaping to Enhance Biological Control: 

  

A first step in ecological pest management is learn more about pests and beneficial insects that may be present in your fields.  The Alabama IPM Communicator contains some valuable information about which pests are present in AL crops and this week Dr. Ayanava Majumdar, Extension Entomologist, begins a series about insect predators:  Know Your Friends:  Alabama IPM Communicator, June 15, 2012. Volume 3, No. 8:

http://www.aces.edu/pubs/docs/I/IPMNEWS-0043/IPMNEWS-0043.pdf

Every week I will post organic-relevant information from the Alabama IPM Communicator. 

Below is the excerpt from this week’s newsletter:

KNOW YOUR FRIENDS:

INSECT PREDATORS—LACEWINGS & LADY BEETLES

By Dr. Ayanava Majumdar

Beneficial insects are an important part of the natural ecosystem and provide a valuable service to crop producers. An acre of crops can have a significantly large number of insect predators and parasites (in fact, according to published scientific literature from Arkansas and California, there can be more species of beneficial insects present in a cropping system than pest species). However, low populations and cryptic behaviors of predators make them appear as if they are ineffective. Through this newsletter section called “Know Your Friends”, I will attempt to familiarize readers with one or two beneficial insect species in every issue and explain their field usage technique as recommended by the industry. Organic as well as conventional farmers should use selective insecticides in a timely manner to minimize impact on the beneficial insect populations.

Sources of beneficial insects:

Numerous vendors sell beneficial insects via their website along with plenty of good information. For example, Arbico Organics (AZ), Orcon (CA), Grow Organic (CA), Gardens Alive (IN), and Nature’s Control (OR) sell insect predators in large numbers and at least one vendor sells it as a ‘beneficial insect program’ with weekly shipments adjusted to your pest control needs. Note that beneficial insects are slow-acting in pest outbreak situation, so use beneficial insects preventively when pests are in low populations and have not overwhelmed the crops you are trying to protect. Follow the release instructions that come with the products and modify your spray schedule to adjust for the presence of beneficial insects.

[Note:   The Beneficial Insect Company in NC is another source for beneficial insects.

http://www.thebeneficialinsectco.com/.]

GREEN LACEWINGS

Many species of lacewings occur naturally in cropping systems. Green and brown lacewings are most common predators of aphids, so they are also known as the ‘aphid-lions’. Green lacewings are larger in size than brown lacewings. Lacewing adults lay eggs singly or in small groups attached to various plant parts. Green lacewing eggs have a stalk to protect the developing larvae from other predators. Brown lacewing eggs do not have a stalk. Lacewing eggs hatch in 3-6 days. Lacewing larvae look like small alligators and have large-sickle shaped mandibles that are used to catch prey. Larvae pierce the body of prey and suck juices. Green and brown lacewing larvae may look similar in appearance with 2 to 4 white spots on the top of body; however, the brown lacewing larvae have a side-to-side ‘head-wagging behavior’ that is not present in green lacewings. Besides aphids, these larvae can feed on whiteflies, caterpillars (fruitworms, loopers, armyworms), and even eggs. Each larva takes about 2 weeks to develop and may feed on 250-300 aphids per week. Green lacewing larvae pupate inside a cocoon attached to plant parts and adults emerge in about 2 weeks. Brown lacewing pupa is elliptical with a loose cocoon through which the pupa is visible. Lacewing adults are good fliers that are strongly attracted to light and can fly many miles immediately after emergence. Adult lacewings have delicate body and transparent wings with many veins visible (‘net-like wings’). Adults feed on pollen and nectar. Female lacewings can lay 200-800eggs and live for many weeks. The green and brown lacewings overwinter as adults but there are other species that can live as pupae during winter. About 2-3 generations may occur every year.

Larva with large
sickle-shaped mandibles

Eggs on stalks glued to a leaf

Pupation inside a cocoon occurs on plants

Adult lacewing with large wings

     

                  

   

           

Image sources: Oregon SU, University of Arkansas, Wikipedia, Iowa SU

Lacewing eggs can be purchased in large numbers from many suppliers. This approach to insect control is called ‘inundative biological control’ as pest management is expected from the released individuals. Alternatively, lacewing eggs may be released in an ‘inoculative approach’ where long-term establishment of the beneficial insect is desired. Due to rapid flight of adult lacewings out of their release site and lack of food, the inoculative approach may not always work on many farms. Therefore, some vegetable producers with high tunnels and greenhouses routinely use lacewings in conjunction with parasitoids for broad-based pest management. Identify the pest first and then purchase the appropriate predator.  [See Dr. McBug’s website for more information about how to keep these beneficial insects around].

Commercial lacewing eggs are packed in bran and the container can be kept refrigerated (not frozen) for several days. Do not transfer contents into another container for storage. Purchase eggs early in the week so they arrive in mail ready for release. A good practice is to check the viability of these eggs by retaining some eggs in a vial at room temperature and let them hatch in captivity. Eggs need to be scattered on plant surfaces while avoiding the presence of other predators like ants (please follow the instructions that come with your purchase). Manufacturers like Arbico Organics recommend 1000 eggs per 2500 square feet. Up to 50,000 eggs may be needed per acre for large scale release.

CONVERGENT LADY BEETLE

This is a very common species of lady beetle among the numerous others present in any crop field. The conver-gent beetle is common in Alabama and also very popular beneficial insect sold by companies, hence is worth discussing here.

The insect name comes from the two white lines seen on the thorax of adult beetles (arrow in picture) that seem to be coming together on the top. The number of dots can vary from none up to 13, so counting the dots alone is not a good identifier for this beetle. Larvae are black with rows of orange spots. Not that the lady beetle larva have chewing mouthparts and do not have the sickle shaped mandibles of the green lacewing larva (previous page). Eggs are elliptical and bright yellow in color; eggs are laid in clusters on plants with over 10 eggs per cluster. Eggs can also be laid in soil or plant debris. Pupae are immobile (nonfeeding stage) and may be seen stuck to plant parts.

Eggs on plant surface

Larva

Pupa

Adult lady beetle

          

                                                                                                       

 Image sources: Univ. of California—Davis, Iowa SU

Adults and larvae feed on aphids. Adult beetles also feed on nectar and pollen. According to industry sources, each adult lady beetle can destroy about 5000 aphids while the larvae can consume nearly 400 aphids in a week. In the absence of aphids, convergent beetles can also feed on moth eggs and small caterpillars. Female convergent beetles lay up to 1000 eggs in ideal conditions and have a lifespan of 1 to 3 months. Larvae feed for 3 weeks and adults emerge 2 to 5 days after pupation. Adults do not fly if air temperatures are below 55F. There can be many generations of this insect every year.

The presence of a large number of lady beetles can indicate the presence of aphids. This insect can be the most abundant predator in cotton fields. Many suppliers sell lady beetles in the adult stage when they are ready for field release. The adult beetles can also be stored in their original package for some duration. Industry sources recommend the release rate of 4500 beetles for 2500 square feet and much larger numbers for large areas. Out migration of adults once prey numbers dwindle is a major cause of loss of these powerful natural control agents. Routine release of beetles in large numbers can be effective in enclosed structures for aphid control.

I will continue to update this discussion of natural predators from the next issues of the IPM newsletter. Remember that parasitoids and pathogens also act in conjunction with predators to provide natural control of pests. Do your own research before purchasing large batches of predators and carefully plan the release for the best effect. Follow the instructions that come with your purchase of beneficial insects. Providing cover crops or shelter plants during fall season is a good way to facilitate continuity of predators in an area.  

In addition to the AL IPM Communicator, below are some very good resources on designing a farm system that attracts and maintains beneficial insect populations.

Additional Resources on Ecological Pest Management

In addition to the AL IPM Communicator, below are some very good resources on designing a farm system that attracts and maintains beneficial insect populations.

How to Get Started with IPM—Planning, Planning, Planning (excerpts from Biointensive Integrated Pest Management):


Good planning must precede implementation of any IPM program, but is particularly important in a biointensive program. Planning should be done before planting because many pest strategies require steps or inputs, such as beneficial organism habitat management, that must be considered well in advance. Attempting to jump-start an IPM program in the beginning or middle of a cropping season generally does not work.
IPM options may be considered proactive or reactive. Proactive options, such as crop rotations and creation of habitat for beneficial organisms, permanently lower the carrying capacity of the farm for the pest. The carrying capacity is determined by factors like food, shelter, natural enemies complex, and weather, which affect the reproduction and survival of a species. Cultural controls are generally considered to be proactive strategies.

The second set of options is more reactive. This simply means that the grower responds to a situation, such as an economically damaging population of pests, with some type of short-term suppressive action. Reactive methods generally include inundative releases of biological controls, mechanical and physical controls, and chemical controls.

Proactive Strategies (Cultural Controls)

• Healthy, biologically active soils (increasing belowground diversity)
• Habitat for beneficial organisms (increasing aboveground diversity)
• Appropriate plant cultivars

Maintaining and increasing biological diversity of the farm system is a primary strategy of cultural control. Decreased biodiversity tends to result in agroecosystems that are unstable and prone to recurrent pest outbreaks and many other problems.  Systems high in biodiversity tend to be more "dynamically stable"—that is, the variety of organisms provide more checks and balances on each other, which helps prevent one species (i.e., pest species) from overwhelming the system.

Creation of habitat to enhance the chances for survival and reproduction of beneficial organisms is a concept included in the definition of natural biocontrol. Farmscaping is a term coined to describe such efforts on farms. Habitat enhancement for beneficial insects, for example, focuses on the establishment of flowering annual or perennial plants that provide pollen and nectar needed during certain parts of the insect life cycle. Other habitat features provided by farmscaping include water, alternative prey, perching sites, overwintering sites, and wind protection. Beneficial insects and other beneficial organisms should be viewed as mini-livestock, with specific habitat and food needs to be included in farm planning.

Examples of how to use farmscaping effectively in your farming system can be found in the references below.  Green lacewings and convergent ladybeetles are generalist predators that feed on a variety of pest insects so they are good beneficial insects to keep around your crops.  Appendix A in Farmscaping to Enhance Biological Control lists plants that attract beneficials.
 
To attract and conserve green lacewings, plant members of the carrot family (caraway, Queen Anne's lace, tansy, dill, angelica), sunflower family (coreopsis, cosmos, sunflowers, dandelion, goldenrod), buckwheat, corn, and provide water during dry spells.

Convergent lady beetles:  Once aphids leave a crop, lady beetles will also.  To retain active lady beetles , maintain cover crops or other hosts of aphids or alternate prey.  Plant members of the carrot family (fennel, angelica, dill, tansy, Queen Anne's lace), sunflower family (goldenrod, coreopsis, cosmos, dandelion, sunflower, yarrow), crimson clover, hairy vetch, grains and native grasses, butterfly weed (Asclepias), black locust, buckwheat, euonymus, rye).

Note from Appendix A that these same plants attract a large variety of beneficial insects.  Also note that these farmscaping plants are already present in most diverse organic agroecosystems as herbs, cut flowers, or cover crops.  By allowing some of these crops to flower they can serve double purposes in your cropping system.

Beneficial organisms should be viewed as mini-livestock, with specific habitat and food needs to be included in farm planning (ATTRA).

Grow Your Own Bugs:  Managing For Beneficial Insects or Plant It and They Will Come!

For information on how you can attract and maintain populations of beneficial insects in your gardens and fields visit the website of Dr. Richard McDonald (aka Dr. McBug):  www.drmcbug.com.

Click on the links at the top of the page for pictures and information on pests, beneficials, and farmscaping plants (plants for the purpose of attracting beneficial insects), epm (ecological pest management), and other valuable sources of information.

Farmscaping for Insect Management: Integrated Parasite/Predator/Pathogen Management & Strategies for Encouraging Beneficial Insects in the Field or "if you plant it, they will come...." Richard McDonald, Ph.D., Symbiont Biological Pest Management, 194 Shull's Hollar, Sugar Grove NC 28679;(828) 297-BUUG (2884); e-mail: the_edge@goboone.net website: www.drmcbug.com. 

Below are excerpts from Dr. McBug’s website:

Farmscaping - Dr. Robert BUGG - Definition: Deliberate use of specific plants and landscaping techniques to attract and conserve "Beneficials". Feed your bugs - Dr. McDonald's Applied Farmscaping Principles:

1) Farmscaping is part of a Multiple Redundant Systems (MRS) approach - MRS is a form of disaster preparedness - triple redundancy is desirable for plants and insects. So for both you want "guilds" of food plants and natural enemies to protect your plants. This is why we list more than 10 beneficial food plants per season - more than one natural enemy attacking each life stage is better, too. Less can lead to breakdowns.

2) Anticipate Pest Problems - Think Ahead - encourage the right beneficial insects to be there when you need them to attack the pests. Ladybugs/trichogramma wasps attack the eggs of caterpillars.

3) Specific Plants attract specific beneficials - example: fennel is great for attracting parasitic wasps, syrphid flies, and ladybugs. So one plant can bring in a guild of beneficials.

4) 5-10% of crop area should be planted in farmscaping plants- "lots of clumps of food plants spread out over an area is much better than one big clump"!

5) Consider Dispersion indices for insects when foraging - "Insect Specs":

Low Dispersion- (Stay in field)	Medium Dispersion (forage 1/4 mile)	High Dispersion (forage > 1/4 mile)
Ground Beetles (Carabids) Ladybeetles (when happy)	Most Parasitic wasps Predatory Wasps - Paper	Syrphids - Hover Flies Dragonflies, Tachinid Flies
Smaller Parasitic Wasps	Predatory Bugs	Larger Parasitic Wasps

6) Have something blooming all the time - Flowers are prime food & mating sites for wasps. Important to have a well fed, mated female beneficial! Green House - use to Jump-start garden areas.

7) Nectar - liquid sugar food + vitamins for beneficials. Nectar is critical for optimum performance of many beneficials. Many beneficials will lay over 3-fold more eggs if properly fed. Example: Parasitic wasps egg laying capacity - poorly fed - 30 eggs; if she is well fed, over 300 high quality eggs. Some of the best plants you can have for this purpose are those in the wild carrot family (also known as Umbellifera), such as dill, fennel, tansy, queen Anne's lace, caraway, coriander, parsnip, etc.

8) Extra-Floral Nectaries - nectar glands that are not associated with flowers. Peonies, Sweet potatoes, bachelor buttons, all have extrafloral nectaries. Parasitic wasps and flies use these extrafloral nectaries as important food sources.

9) Pollen - Is an alternative form of protein. Once again, many plants in the wild carrot family can provide pollen. Another good pollen producer is the corn plant. Syrphid flies need pollen to lay eggs.

10) Overwintering sites for beneficials - It turns out that many beneficials make cocoons and hibernate in or very near the plants where they find their hosts. Recent research has shown that yarrow and comfrey are also excellent overwintering plants for parasitic wasps.

11) Entrainment - (entomologists- Joe Lewis really opened up this field) have discovered that insects (especially parasitic wasps and flies) can perform associative learning, so if you get insects (especially young ones) happy in their environment, they will "tune in" to a particular pest. A good way to do this for a predator or parasite is to release it on or nearby the intended prey.

12) Drought/Stress - These systems can also fail! In drought years insects from all over will come to your area and can overwhelm a system. Be ready with backups additional insects,ladybugs/lacewings, Bt, soaps, diatomaceous earth. Save the soap/de for last, because they kill anything. Finally,

13) Your Design Decisions Mantra: Encourage Biodiversity! - Remember that insects are part of the web of life in your garden or farm. The beneficial insect complex is not only composed of parasitic wasps and flies, predatory beetles, lacewing larvae, ladybugs and so on, but ALSO the pollinators, antagonists/competitors that occupy and compete for space and food with potential pests, and finally the saprophytes and decomposing insects that help complete the food cycle back to the soil so the cycle can start again. And remember, "If you plant it, they will come...." For further information on Farmscaping, go to my web site (www.drmcbug.com) and click on the farmscaping section. Also see ATTRA's Farmscaping publication at their website (www.attra.org).

The gist of this message is that, just like us, beneficial insects need sources of food and shelter in order to stick around. You can weave "web of life" in your garden/farm by planting specific plants that attract specific beneficials. Also, by thinking ahead and anticipating the types of pest problems you might have, you can encourage the right beneficial insects to be there when you need them to attack the pests. My motto is: "If you plant it, they will come. Or, I will buy them (beneficials) once and have them here forever after..."

FARMSCAPING - Top Plants for Beneficials 
Spring: brassicas - ground ivy, wild mustards, Tulip poplar, vetches, pussy willow, yarrow, umbels - parsley/parsnip/ coriander, buckwheat, clovers, mints, Norway Maple, grains, peonies, borage.
Summer: mints, wild carrots- cow parsnip, tansy, bronze fennel, smartweed-Vietnamese Cilantro, Jerusalem artichoke, kenafe, sweet potato, borage, smartweed, bachelor buttons.
Fall: Patrina, Autumn joy sedum, vetches, chrysanthemum (Pacifica), tansy, bronze fennel, Queen Anne's Lace/other wild carrot family plants, garlic chives, Goldenrod, yarrow, comfrey and some of the last broccoli for overwintering on/underneath.

Top Beneficials
1. Ladybugs 2. Predatory Bugs - Big-Eyed/Nabid(Damsel)/Assassin/Stink/Pirate(Orius) Bugs. 3.Syrphid Flies 4. Parasitic wasps 5. Lacewings 6. Parasitic flies 7. Ground beetles 8. Spiders 9. Mantids 10. Dragonflies

Common Pests that we can control:
1. Whiteflies 2. Flea beetles 3. Spider Mites 4.Cucumber beetles 5. Aphids 6. Japanese beetle/Exotic scarabs 7. Squash Vine Borers 8. Cabbage Caterpillars 9. Mexican Bean Beetle 10. Stink bugs

Other resources for Ecological Pest Management:

USDA Alternative Farming Systems Information Center:

http://afsic.nal.usda.gov/ecological-pest-management/biological-control

University of California, Riverside: BIOLOGICAL-INTEGRATED PEST MANAGEMENT & INSECT IDENTIFICATION

http://faculty.ucr.edu/~legneref/bc.htm

Biointensive Integrated Pest Management:  National Sustainable Agriculture Information Center:

https://attra.ncat.org/attra-pub/summaries/summary.php?pub=146

Farmscaping to Enhance Biological Control:  National Sustainable Agriculture Information Center:  https://attra.ncat.org/attra-pub/summaries/summary.php?pub=145