Graduate Research Assistant Purdue University West Lafayette, Indiana
The evergreen bagworm (Thyridopteryx ephemeraeformis Haworth) (Lepidoptera: Psychidae) was tested for impact of microclimate warming on its overwintering survival. The European fruit lecanium (Parthenolecanium corni Bouché) was tested for its reproduction capacity during summer time. We predicted that impervious surface resulted microclimate warming could keep canopy temperature warm enough to improve bagworm survival in Indiana and Illinois. Similarly, summer reproduction of scale insect was evaluated on honeylocust tree in Indianapolis, Indiana. A total of 1303 and 952 bagworms were collected in 2018 and 2019 respectively with latitude ranging from 39.93 to 41.47. For scale insect sampling, four branches having 30.5 cm length were sampled from 48 honeylocust trees during June 3, 2019 and June 7, 2020 when accumulated growing degree day was 700 at 50°C base temperature. Impervious surface within a 20 m radius of each host tree was estimated by pace to plant technique. In overwintering survival test, the survival of egg masses depends on amount of impervious surface around the host trees. Increased impervious surface area around the tree increased the tree canopy temperature. In summer reproduction of scale insect test, microclimate warming improved the reproduction capacity of female scale insect. Therefore, impervious surface around host trees can create a temperature buffer zone to create microclimate warming which can improve both overwintering survival and summer reproduction of insect pests in urban areas.
