Biological Pest Control and Valencia Oranges

There are huge concerns about the use of chemicals in controlling agricultural pests that destroy crops. Nearly every crop you can think of has a worm, fungus, or bug that eats it and can wipe out a significant food source for humans. Since World War II, this problem is usually addressed by using chemicals to kill the offending pest. The problem is the collateral damage of agricultural chemicals, and the solution is biological pest control which actually predates industrial pesticides.

We know now that many of these chemicals cause cancer in human beings. We have also seen the terrible effects of chemicals on wildlife. In past years, the use of DDT on various crops resulted in the death of massive numbers of birds. Fish populations in fresh and seawater have been decimated by runoff from fields sprayed with pesticides. The real tragedy is that the use of chemicals is almost unnecessary. God has provided solutions to the problem of agricultural pests, but humans refuse or neglect to use those solutions.

More than a century ago, the first instance of modern biological pest control was the decimation of citrus groves by a bug named Icerya. The Icerya probably came to America from their native Australia by hitchhiking with careless travelers. In California, some 600,000 orange trees produced Valencia oranges in 1890 until Iceryas invaded and decimated them, reducing orange production by 80%.

Growers tried every method they could think of, including spraying the remaining trees with chemicals, setting off explosions, and burning infected trees. Finally, entomologists went to Australia and discovered a ladybug known as Novius that eats Icerya. When growers released the ladybugs in the California citrus groves, they wiped out the Icerya and rescued the American orange crop.

Citrus growers still depend on Novius ladybugs and pay up to a dollar per ladybug when they have Icerya infestations in their trees. God’s natural biological pest control works with no cancer risk and minimum cost. Unfortunately, human impatience with God’s answers has caused cancer, pollution, and enormous environmental damage.

— John N. Clayton © 2022

Reference: Smithsonian magazine January/February 2022 pages 22 – 25.