Pesticide resistance is a major problem that occurs when a pesticide is used for control for years and then will no longer kill the pest. This is a billion dollar problem for US agriculture.
In 1999 the cost of pesticides and the yield loss of crops to pesticide resistance was estimate at $1.5 billion in the US alone. In 1996 it was estimated that over 500 insects were resistant to one or more pesticides commonly used to control them. There were also 270 weed species, over 150 plant pathogens and a half-dozen species of rats that were resistant. Those numbers have only grown in the last 15 years.
There is even a common name for this problem. It is called the “pesticide treadmill”. It is called a treadmill because once it starts to develop people apply more pesticide which causes more resistance. So more pesticide is applied and even more resistance develops.
In some places in the world mosquitoes that spread malaria are resistant to all pesticides known to control them. Pigweed, the most common weed in cotton fields is resistant to the active ingredient in the herbicide Roundup. In Florida in 2002 somewhere between 10 and 50 sites the aquatic plant hydrilla is no longer controlled by the preferred herbicide. This forces use of a more expensive herbicide to control it cost taxpayers more.
- You can help by applying pesticides responsibly:
- Use mechanical methods
- Use natural products
- Only use chemical pesticides as a last resort and then do spot treatments.
- Only use a pesticide that has your pest on its label.
- Find pest tolerant plants to use in your garden.
- Clean up debris and dead leaves from around plants to reduce habitat for insects.
- When mixing pesticides from concentrate; follow the directions.
- If you use chemical pesticides, rotate among a variety to as not to develop resistance.