What is the recommended threshold for applying insecticide when monitoring sod webworms on turf?

What is the recommended threshold for applying insecticide when monitoring sod webworms on turf?

• A. Two to four webworms per square foot
• B. More than ten per square foot
• C. One per square yard
• D. Five to six per square foot

Answer: (A)

The question tests understanding of the economic threshold for insecticide use in turf. For sod webworms, you scout and count larvae in a defined area to decide when control is warranted. When you find about two to four webworms per square foot, that level is enough to cause meaningful turf damage and justifies applying insecticide because the potential benefit fits the cost of treatment. Below this density, natural controls and lower risk of damage mean you can wait or monitor rather than spray. Above this range, damage risk escalates and timely treatment becomes more necessary. The other options misrepresent the practical scouting scale or imply densities that are either far too low, far too high, or not measured in the standard square-foot units, making them less reliable for guiding action.

The question tests understanding of the economic threshold for insecticide use in turf. For sod webworms, you scout and count larvae in a defined area to decide when control is warranted. When you find about two to four webworms per square foot, that level is enough to cause meaningful turf damage and justifies applying insecticide because the potential benefit fits the cost of treatment. Below this density, natural controls and lower risk of damage mean you can wait or monitor rather than spray. Above this range, damage risk escalates and timely treatment becomes more necessary. The other options misrepresent the practical scouting scale or imply densities that are either far too low, far too high, or not measured in the standard square-foot units, making them less reliable for guiding action.