To study prevalence of brown marmorated stink bug in trees, researchers led by Nicole Quinn at Virginia Tech placed pheromone-baited pyramid traps in trees (tree of heaven, Ailanthus altissima, shown here) near the ground, mid-canopy, and near the top of the canopy. Combined with felling trees to collect stink bug egg masses, the researchers found greater stink bug presence in the middle and upper levels, and stink bug egg masses parasitized by the wasp Trissolcus japonicus were found only in middle and upper levels, as well. (Images originally published in Quinn et al 2018, Environmental Entomology)