Sequential sampling plans for the hairy chinch bug (Hemiptera: Lygaeidae)

Area of Science:

• Agricultural Entomology
• Pest Management
• Turfgrass Science

Background:

• Hairy chinch bug (Blissus leucopterus hirtus Montandon) infestations are a significant concern for turfgrass health in Quebec, Canada.
• Current pesticide-based control methods necessitate more efficient and targeted strategies to minimize environmental impact.
• Developing reliable sampling plans is crucial for accurate pest assessment and informed management decisions.

Purpose of the Study:

• To develop and validate sequential sampling plans for the hairy chinch bug on turfgrass in Quebec's cool-humid region.
• To provide practical tools for reducing pesticide application in turfgrass management.
• To compare the efficacy of sampling plans based on Wald's and Iwao's methods.

Main Methods:

• Development of two sequential sampling plans: one using Wald's method and another using Iwao's method.
• Validation of sampling plans on naturally infested turfgrass lawns.
• Visual sampling of 0.1-m2 quadrats to assess chinch bug distribution and density.
• Estimation of infestation occurrence and calculation of error rates (alpha and beta).

Main Results:

• Wald's sampling plan proved too conservative during validation.
• Iwao's sampling plan yielded effective results, with error rates (alpha < 0.05, beta < 0.14) below acceptable limits.
• Hairy chinch bug infestations were estimated at 28% in the Montreal and Quebec City regions.
• The Iwao plan requires approximately 20 minutes for a single-person lawn evaluation.

Conclusions:

• The Iwao-based sequential sampling plan is a precise and practical tool for managing hairy chinch bug infestations in turfgrass.
• This method can significantly aid in reducing pesticide use, particularly in regions with less than two chinch bug generations per season.
• The plan's effectiveness suggests its adoption as an essential component of integrated pest management strategies for turfgrass lawns.