Influence of deployment method and maintenance on efficacy of sticky card traps for <i>Halyomorpha halys</i> (Hemiptera: Pentatomidae)

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is an invasive pest which feeds on numerous economically significant crops. Many integrated pest management strategies for this species rely on effective season-long monitoring for H. halys populations, including attract-and-kill and threshold-based insecticide sprays. Previous studies have shown that a black pyramid trap effectively captures all mobile life stages of H. halys, however, these bulky, ground-deployed traps can be impractical in active orchard rows. Clear sticky cards have been used as a more practical tool for monitoring when paired with the H. halys aggregation pheromone and synergist. Here, the efficacy of deploying single- or double-sided sticky cards hanging in trees or deployed on wooden stakes was compared to standard black pyramid traps over 2 years. The efficacy of single-sided sticky cards deployed on wooden stakes was also evaluated after occlusion of 25%, 50%, or 75% of the surface area by 2D inert materials and 3D organic matter. Single-sided sticky cards were also exposed to simulated sunlight and rainfall for 0, 4, 8, and 12 wk before deployment on wooden stakes. Captures of H. halys adults using sticky cards deployed on wooden stakes were comparable to pyramid traps. Occlusion of cards by 25% or more of any material type led to a decrease in H. halys captures, however, weathering did not influence capture. These data show that clear sticky cards deployed on wooden stakes are effective for season-long monitoring of H. halys in apple orchards, and card replacement should be driven by maintenance of cleanliness.