Effects of soil pot conditions on Laricobius nigrinus emergence rates.

Hemlock Wooly Adelgids (Adelges tsugae), or HWA, are invasive insects that feed on native Eastern Hemlocks (Tsuga canadensis). Trees have limited defenses against these insects, and there are no native predators or parasites that consume HWA. Populations of Eastern Hemlocks have been devasted along the eastern North American coast as the invasive has spread, impacting both terrestrial and riparian communities.  Fortunately, efforts to breed and release non-native, predator beetles that specialize on HWAs have shown to be an effective biological control. One of these beetles, Laricobrius nigrinus, or Ln, feeds on HWA throughout its established range, however, efforts to breed these beetles in captivity have been minimally successful with maximum emergence rates of 30%.This pilot study aimed to improve Ln breeding procedures by comparing the emergence rates of different sized containers. Five small soil pots (estimate volume) were paired with five large soil pots (estimate volume). Ten Ln larva were place in each soil pot and the UNG PBL Protocol for Rearing Laricobius nigrinus was followed throughout the experiment. Of 100 larvae, only four successfully emerged as adults. Due to the low emergence, no conclusions can be made comparing small soil pots to large soil pots. However, the challenges of captive rearing Ln were exemplified, giving direction to future studies with respect to the Ln rearing procedure.