Illinois Field Crop Applicators Practice Test

What type of method do the following control strategies represent? - Tachinid flies parasitizing army worms.

1. Biological

2. Cultural

3. Mechanical

4. Chemical

The correct answer is: Biological

The scenario describes tachinid flies that parasitize army worms, which clearly illustrates a biological control strategy. Biological control involves the use of living organisms to suppress pest populations. In this case, tachinid flies are natural predators of army worms; they contribute to reducing the population of these pests through parasitism. This method is appealing because it utilizes the natural predatory behavior of one species to manage another, which can lead to more sustainable pest management practices. Biological control is often favored in integrated pest management systems because it tends to have fewer negative impacts on the environment compared to chemical control options, reducing the reliance on synthetic pesticides. Other control strategies like cultural, mechanical, and chemical control do not apply here as effectively. Cultural control involves practices such as crop rotation and field sanitation, which do not involve living organisms. Mechanical control includes physical methods like traps and barriers, while chemical control relies on the use of pesticides to eliminate pests directly. In this case, since the control method directly involves a natural organism acting against a pest, it is classified as biological control.