The term "beneficials" refers to those insects that "benefit" a plant. Sounds so simple, but the way in which they benefit plants is not so simple and is, in fact, a fascinating component of integrated holistic agriculture. The use of beneficials to protect plants requires intimate knowledge of the life cycle and habit of these insects. Farmers can’t just let loose a horde of labybugs in the hopes that they will devour all those darned aphids even though a ladybug can eat up to 4,000 during its life. But then what does the farmer do with all those happy, fat, well-fed ladybugs? This unexpected infusion of insect life into an ecosystem can upset the natural balance and possibly be as problematic as the aphids.
Some organic gardeners at home bemoan the fact that they import beneficials onto their property only to find they have disappeared into the neighborhood. You can’t put a leash on a ladybug. The farmer has to know what he’s doing and what he’s working with when employing the use of beneficials, or he will spend time and money to no good end.
Beneficials work in different ways – they fall into one of three categories: predators, parasitoids and pollinators. Predators serve to protect plants by attacking other insects which are harming plants. Parasitoids serve the same purpose, but they live on or in a host insect, eventually killing it. Pollinators pollinate. About 90 or more crops are pollinated by honey bees alone – crops such as apples, blueberries, peaches and pears. Along with ladybugs and honey bees, you will find that the list of beneficial insects includes dragonflies, aphid midges, assassin bugs, lacewing wasps, praying mantis, spiders, parasitic wasps and flies.
The organic farmer encourages the natural introduction of beneficials by providing a hospitable habitat and keeping the land clean of chemicals. Beneficials can easily be repelled or killed by insecticides and pesticides. These products do not discriminate and will kill the good bugs along with the bad.
Certain plants attract beneficials so farmers sometimes plant them on the property for this purpose. The carrot family (Umbelliferae), for example, offers pollen and nectar for beneficial insects.
A healthy crop can more easily fight off attack from harmful insects. Organic crops are, by their very nature, healthier than conventional crops. Matching crops to the location will go a long way towards ensuring health all round. Incorporating beneficials into the mix is just one way of protecting crops.
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