Natural Approach

Article from Alaska Airlines Magazine by Kerry Duff

Nothing bugs Don and Leah of Tucson Arizona, more than the use of chemical pesticides to ward off creepy critters. They believe in using natural predators such as ladybugs, nematodes, praying mantis and green lacewings. They offer more than 50 species of natural predators through their Internet-based business. Buglogical Control Systems, Inc. launched in 1996 after becoming concerned about the harmful effects of pesticides on children and the environment. “We’re now finding out in this country that pesticides thought to be safe 10 years ago are harmful, “says Don. “So more people are starting to warm up to the idea of natural beneficial insects and using organic products.” Beneficial bugs take a little longer than pesticides to begin working, but they do work, “Whereas using chemicals also kills the good beneficial insects and its use is not save for the environment. Most insects will build up resistance to pesticides, and eventually more and more chemicals have to be used for the same effect.”

Buglogical’s customers range from homeowners, schools, universities, United States department of agriculture, state parks, county parks, city parks, amusement parks, greenhouses, greenhouses, golf courses, organic farms, Disney world, and resorts.

Don and Leah attribute Buglogical’s growth to increasing public awareness in the use of beneficial insect and providing good information to our customers in the type of beneficial insects needed for their garden and farm. Customer service is their highest priority in providing information and live delivery of their insects.

Insects are the dominant life-form on earth. Millions may exist in a single acre of land. About one million species have been described, and there may be as many as ten times that many yet to be identified. Of all creatures on earth, insects are the main consumers of plants. They also play a major role in the breakdown of plant and animal material and constitute a major food source for many other animals.

Insects are extraordinarily adaptable creatures, having evolved to live successfully in most environments on earth, including deserts and the Antarctic. The only place where insects are not commonly found is the oceans. If they are not physically equipped to live in a stressful environment, insects have adopted behaviors to avoid such stresses. Insects possess an amazing diversity in size, form, and behavior.

It is believed that insects are so successful because they have a protective shell or exoskeleton, they are small, and they can fly. Their small size and ability to fly permits escape from enemies and dispersal to new environments. Because they are small they require only small amounts of food and can exist in very small niches or spaces. In addition, insects can produce large numbers of offspring relatively quickly. Insect populations also possess considerable genetic diversity and a great potential for adaptation to different or changing environments. This makes them an especially formidable pest of crops, able to adapt to new plant varieties as they are developed or rapidly becoming resistant to insecticides.

Insects are directly beneficial to humans by producing honey, silk, wax, and other products. Indirectly, they are important as pollinators of crops, natural enemies of pests, scavengers, and food for other creatures. At the same time, insects are major pests of humans and domesticated animals because they destroy crops and vector diseases. In reality, less than one percent of insect species are pests, and only a few hundred of these are consistently a problem. In the context of agriculture, an insect is a pest if its presence or damage results in an economically important loss.

The adage "know your enemy" is especially appropriate when it comes to insect pests. The more we know about their biology and behavior, including their natural enemies, the more likely we will be able to manage them effectively.

DON'T BUG ME Waynesburg greenhouse owners turn to mother nature - rather than pesticides - to rid their plants of unwanted visitors

By Jon Stevens, Staff writer

WAYNESBURG - No one can argue it's a good thing that businesses and governments are becoming more environmentally conscious to ensure the sustainability of the planet. "Going green," a trend, concept or movement, is becoming a catch-all phase for making our lives better. "Green" is everywhere these days - in the news, politics, fashion and even technology. It can be easy to get caught up in the everyday stuff - switching to organic foods, turning down the thermostat, recycling ... the list goes on.

Now, we see green in the greenhouse where Ethan and Dawn Phillips, owners of Mother Earth Farm greenhouse at the intersection of Routes 221 and 19 in Ruff Creek, Greene County. They have committed to make their plants and flowers "earth friendly" by abandoning the use of pesticides and incorporating nature's own defense against harmful insects. In other words, they are using bugs that eat bugs. The Phillipses begin their plantings in several greenhouses about a mile-and-a-half away from the retail greenhouse on Locust Road, off Route 221.

The tube-like cocoons are semi-naked now, but flats of varieties of flowers, plants and vegetables soon will cover the rows and rows of tables before the mature plants are taken to their retail greenhouse. "We don't spray with pesticides anymore," Ethan said, "because many of the insects that attack the plants have become resistant."

Dawn said the chemicals are neither consumer nor environmentally friendly. So, Dawn ordered 9,000 ladybugs and some encarsia formosa (whitefly-eating wasps) to keep the insects that attack their plants under control. The bugs the Phillipses purchased from are expected to eat and destroy pests such as aphids, thrips, mites, scale and whitefly populations. Also called to duty to guard the Phillipses' livelihood are their dog, Susie, and two black cats. "Susie, who came from the Greene County Humane Society, is responsible for keeping out the raccoons. So far, she has dispatched two of them. The cats, as you would expect, take care of the mice," Dawn said.

The couple recognize that in raising flowers, vegetables or otherwise, they are engaged in a constant battle. And the primary enemy are the aphids, sneaky and inconspicuous little beasties. They can show up, breed like crazy and destroy flowers, vegetables and even trees before you ever realize there's a problem. And that is where the ladybugs come in. "When we used pesticides, we had to wear protective gear, take the animals out of the greenhouse and remove their food. This process was just not time-friendly," Dawn said. With the ladybugs, all she has to do is shake some of the bugs on a plant and let them do their work. According to the buglogical website, ladybugs are capable of consuming up to 50 to 60 aphids per day but will also eat a variety of other insects and larvae, including scales, mealy bugs, leaf hoppers, mites and various types of soft-bodied insects. Also, ladybugs are natural enemies of many insect pests, and it has been demonstrated that a single ladybug may consume as many as 5,000 aphids in its lifetime. Dawn said ladybugs search for food from dawn to dusk. Ladybugs are shipped in the adult stage and when released should mate and lay eggs within eight to 10 days. This particular batch arrived in a bag, or two or three, and most of them have been sprinkled onto vulnerable plants. "We realize there may not be a 100 percent eradication of these pests," Dawn said. "But our customers can be assured when they take a plant home, no pesticide was used on it."This will be the fifth year the Phillipses have operated Mother Earth Farm. They started with a large garden on the family farm in Ruff Creek. In 2006, they built their first greenhouse, and in 2007 opened for their first spring season selling bedding plants, hanging baskets and vegetables in Ruff Creek.

Biological Control This segment includes several paragraphs with general information about biological control and these subsections: Biological control is a component of an integrated pest management strategy. It is defined as the reduction of pest populations by natural enemies and typically involves an active human role. Keep in mind that all insect species are also suppressed by naturally occurring organisms and environmental factors, with no human input. This is frequently referred to as natural control. This guide emphasizes the biological control of insects but biological control of weeds and plant diseases is also included. Natural enemies of insect pests, also known as biological control agents, include predators, parasitoids, and pathogens. Biological control of weeds includes insects and pathogens. Biological control agents of plant diseases are most often referred to as antagonists.

Predators, such as lady beetles and lacewings, are mainly free-living species that consume a large number of prey during their lifetime. Parasitoids are species whose immature stage develops on or within a single insect host, ultimately killing the host. Many species of wasps and some flies are parasitoids. Pathogens are disease-causing organisms including bacteria, fungi, and viruses. They kill or debilitate their host and are relatively specific to certain insect groups. Each of these natural enemy groups is discussed in much greater detail in following sections.

The behaviors and life cycles of natural enemies can be relatively simple or extraordinarily complex, and not all natural enemies of insects are beneficial to crop production. For example, hyperparasitoids are parasitoids of other parasitoids. In potatoes grown in Maine, 22 parasitoids of aphids were identified, yet these were attacked by 18 additional species of hyperparasitoids. This guide concentrates on those species for which the benefits of their presence outweigh any disadvantages. A successful natural enemy should have a high reproductive rate, good searching ability, host specificity, be adaptable to different environmental conditions, and be synchronized with its host pest. A high reproductive rate is important so that populations of the natural enemy can rapidly increase when hosts are available. The natural enemy must be effective at searching for its host and it should be searching for only one or a few host species. Spiders, for example, feed on many different hosts including other natural enemies. It is also very important that the natural enemy occur at the same time as its host. For example, if the natural enemy is an egg parasitoid, it must be present when host eggs are available. No natural enemy has all these attributes, but those with several characteristics will be more important in helping maintain pest populations.

There are three broad and somewhat overlapping types of biological control: conservation, classical biological control (introduction of natural enemies to a new locale), and augmentation. Conservation The conservation of natural enemies is probably the most important and readily available biological control practice available to growers. Natural enemies occur in all production systems, from the backyard garden to the commercial field. They are adapted to the local environment and to the target pest, and their conservation is generally simple and cost-effective. With relatively little effort the activity of these natural enemies can be observed. Lacewings, lady beetles, hover fly larvae, and parasitized aphid mummies are almost always present in aphid colonies. Fungus-infected adult flies are often common following periods of high humidity. These natural controls are important and need to be conserved and considered when making pest management decisions. In many instances the importance of natural enemies has not been adequately studied or does not become apparent until insecticide use is stopped or reduced. Often the best we can do is to recognize that these factors are present and minimize negative impacts on them. If an insecticide is needed, every effort should be made to use a selective material in a selective manner.

Classical biological control In many instances the complex of natural enemies associated with an insect pest may be inadequate. This is especially evident when an insect pest is accidentally introduced into a new geographic area without its associated natural enemies. These introduced pests are referred to as exotics and comprise about 40% of the insect pests in the United States. Examples of introduced vegetable pests include the European corn borer, one of the most destructive insects in North America. To obtain the needed natural enemies, we turn to classical biological control. This is the practice of importing, and releasing for establishment, natural enemies to control an introduced exotic pest, although it is also practiced against native insect pests. The first step in the process is to determine the origin of the introduced pest and then collect appropriate natural enemies from that location or similar locations associated with the pest or closely related species. The natural enemy is then passed through a rigorous quarantine process, to ensure that no unwanted organisms are introduced, then reared, ideally in large numbers, and released. Follow-up studies are conducted to determine if the natural enemy successfully established at the site of release, and to assess the long-term benefit of its presence. Classical biological control is long lasting and inexpensive. Other than the initial costs of collection, importation, and rearing, little expense is incurred. When a natural enemy is successfully established it rarely requires additional input and it continues to kill the pest with no direct help from humans and at no cost. Unfortunately, classical biological control does not always work. It is usually most effective against exotic pests and less so against native insect pests. The reasons for failure are often not known, but may include the release of too few individuals, poor adaptation of the natural enemy to environmental conditions at the release location, and lack of synchrony between the life cycle of the natural enemy and host pest. Augmentation This third type of biological control involves the supplemental release of natural enemies. Relatively few natural enemies may be released at a critical time of the season.  

Additionally, the cropping system may be modified to favor or augment the natural enemies. This latter practice is frequently referred to as habitat manipulation. An example of inoculative release occurs in greenhouse production of several crops. Periodic releases of the parasitoid, Encarsia formosa, are used to control greenhouse whitefly, and the predaceous mite, Phytoseiulus persimilis, is used for control of the two-spotted spider mite. Lady beetles, lacewings, or parasitoids such as Trichogramma are frequently released in large numbers (inundative release). Recommended release rates for Trichogramma in vegetable or field crops range from 5,000 to 200,000 per acre per week depending on level of pest infestation. Similarly, entomopathogenic nematodes are released at rates of millions and even billions per acre for control of certain soil-dwelling insect pests.

Habitat or environmental manipulation is another form of augmentation. This tactic involves altering the cropping system to augment or enhance the effectiveness of a natural enemy. Many adult parasitoids and predators benefit from sources of nectar and the protection provided by refuges such as hedgerows, cover crops, and weedy borders.

Weeden, C.R., A. M. Shelton, and M. P. Hoffman. Biological Control: A Guide to Natural Enemies in North America.

United States Department of Agriculture USDA Biological Control Information on Pests and Diseases click here