[Spatial pattern relationships between emerald ash borer larvae and their natural enemies]

Area of Science:

• Forest entomology
• Invasive species ecology
• Pest management

Background:

• The emerald ash borer (EAB) is a destructive invasive insect impacting ash tree populations.
• Understanding the spatial distribution of EAB and its natural enemies is vital for effective control strategies.

Purpose of the Study:

• To investigate the spatial distribution patterns of emerald ash borer larvae, the parasitoid Spathius agrili, and woodpecker activity in ash forests.
• To determine the preferred vertical and horizontal distribution ranges for EAB and its natural enemies.

Main Methods:

• Spatial analysis of EAB larvae, Spathius agrili, and woodpecker pecks within ash forest ecosystems.
• Statistical modeling to describe horizontal and vertical distribution patterns.

Main Results:

• EAB larvae, Spathius agrili, and woodpecker pecks followed a negative binomial distribution in the horizontal direction.
• EAB larvae were found on ash trunks from ground level up to 3.37 m, with a peak distribution around 1.50 m.
• Natural enemies of EAB also concentrated their activity within this preferred vertical range.

Conclusions:

• The spatial distribution of EAB and its natural enemies is non-uniform and concentrated within specific vertical strata on ash trees.
• This concentrated distribution may inform targeted management interventions for emerald ash borer control.