Harnessing Nature To Fight Pests In Organic Farms

In the last few years, research on organic agricultural ecosystems, or integrated pest management, has grown. Some key findings and refined techniques are being used by organic growers.

There’s a small burst of new research into organic farming techniques as a result of America’s 2008 farm bill, which finances agricultural program at a total cost of US$ 307 billion dollars. For years such research was financed at US$ 3 million dollars a year.

And there’s now a growing understanding among organic farmers of ways how to harness nature to fight pests.
A paper published in Nature this year confirmed what organic farmers have long suspected, that conventional farming can make the pest problem worse.

Natural enemies are key to the organic approach. One of the most difficult pests to deal with is the lettuce aphids. The treatment of choice for commercial organic lettuce is to plant an ornamental flower called alyssum among lettuce beds, taking up 5 to 10 percent of the total field.

Hoverflies live in the alyssum and need a source of aphids to feed their young, so they lay their eggs on the lettuce. When they hatch the larvae starts preying on the aphids. It said that one larvae per plant control the aphids.

Organic researchers are also studying the role of soil fertility in pest control. Some studies show nutrient rich soil may enhance the plant’s immune system and increase natural resistance to insects and pests or provide a home to natural enemies.

Not all predators are bugs. Rachel Long has studied bats and their role in pest management for 15 years. By studying DNA in bat waste, she found that bats ate moths and other insects harmful to orchards.

Organic farmers aren’t averse to all chemical sprays. Some are from a blend of water and oils from strong and smelling plants like clove, mint and rhyme. Studies in Canada show that they can be effective.

As for weeds, the biggest help there may also be cover crops, things like rye and fava beans. The search continues for a blend of systems that will grow food naturally and be good for nature.