Beneficial Nematodes
By Bruce Lee Deuley - 11/18/02

Many insect pests have developed resistance to pesticides and new pests have positioned themselves where others have been successfully controlled.

The misuse of chemical pesticides have reduced or eliminated many of the natural insect control agents Mother Nature had in place. In addition there is a well-founded concern about pesticide safety and the environment.

All of this has caused the use of beneficial nematodes and other biological controls to gain in popularity. Beneficial Nematodes are microscopic un-segmented worms that prey on the eggs and larva of many species of insects.

Though they are harmless to humans, animals, plants, and healthy earthworms. Beneficial nematodes aggressively pursue insects. By sensing the temperature and carbon dioxide emissions of soil-borne insects, beneficial nematodes move toward their prey and enter the pest through its body openings. The nematodes carry an associated bacterium that kills insects really fast usually within 48 hours.

The bacteria used by the beneficial nematodes are harmless to humans and other organisms and cannot live freely in nature. Several generations of nematodes may live and breed within the dead pest; they emerge and seek more pests in the soil.

Beneficial nematodes are so effective in the soil because they work to kill the immature stages of garden pests before they become adults.

Because they are alive, they must be handled properly to maintain their effectiveness. Usually they are stored on a sponge, in sphagnum moss or in a gel and kept in a cool environment until they are to be distributed in to the soil of a lawn or garden.

Since soils here in the hill country seldom if ever freeze, Beneficial Nematodes can be put out year around. They are most effective when the soil has a bit of moisture in it, which means they probably do their best work here in the spring and fall of the year. But if there are adequate number of "pests-host" in the soil, they will continue to
reproduce year around.

Among the insects they control are fire ants, fleas, ticks and grubworms along with a list of over 200 more potential hosts. Used correctly, beneficial Nematodes can control most all of our more common soil-borne pest with out the use of harmful and many times dangerous chemical pesticides.

Thanks to local cable channel Htv10 here in Kerrville, where I do a weekly organic gardening Show from 9:30 to 10:30 each Saturday morning, you can view all of my articles @ www.htv10.com/nature along with a copy of my Organic Gardening Book.

Next week we will consider several natural fire ant controls.