The InsectXaminer short video series hopes to increase the visibility of the beautiful world of insects, even those we consider to be pests in our managed landscapes. InsectXaminer will showcase the complexity of insect life cycles, cataloging as many life stages for each species as possible. The goal of this series is to provide professionals and land managers with footage that is helpful for learning the identification of insects throughout the season, rather than at any single point in their life cycle. Proper identification is key to successful management. If possible and caught on camera, important aspects of their biology and natural enemies will be revealed.
Join UMass Extension as we observe these incredible organisms and look into a world that, while it happens all around us, sometimes goes unseen!
Lymantria dispar has been in Massachusetts since the 1860's. This invasive insect from Europe often goes unnoticed, thanks to population regulation provided by the entomopathogenic fungus, Entomophaga maimaiga, as well as a NPV virus specific to Lymantria dispar caterpillars. (And to a lesser extent many other organisms, including other insects, small mammals, and birds who feed on Lymantria dispar.) However, if environmental conditions do not favor the life cycle of the fungus, outbreaks of these caterpillars are possible. (Such as most recently from 2015-2018, with a peak in the Lymantria dispar population in 2017 in Massachusetts.) Egg masses, caterpillars, pupae, and adults are showcased here. Certain aspects of field identification of fungus and virus infected caterpillars is also included.
Lily leaf beetle was first reported in the United States in 1992 in Cambridge, MA. This invasive insect from Europe and Asia is a pest of true lilies (Lilium spp.) and fritillarias (Fritillaria spp.). Daylillies (Hemerocallis spp.) are not hosts for lily leaf beetle. While this insect can be found on other plants (Solomon's seal, hostas, and others), it is not known to reproduce and complete its life cycle on these species and causes little damage. On true lilies, however, it can be a significant pest and cause extensive damage to many susceptible species and hybrids. Eggs, larvae, and adults are showcased here. Pupation occurs in the soil. An interesting defense strategy of the larvae is shown.
The euonymus caterpillar was first reported in North America in 1967 in Ontario. This non-native insect is from Europe and is a pest of Euonymus spp. hosts such as European spindle tree (Euonymus europaea), spreading euonymus (E. kiautschovicus), and winged euonymus/burning bush (E. alatus). Interestingly enough, many of these species of euonymus are considered to be invasive plants. Larvae (caterpillars) feed on the leaves of these plants and can completely or partially defoliate their hosts. Extensive webbing created by the caterpillars is shown in a forest understory in Hampshire County, MA that was first invaded by the Euonymus spp. and then taken advantage of by the caterpillars. An infested specimen tree is also shown at a different location. Euonymus caterpillars mature into flying adult spindle ermine moths. Larvae, pupae, and adults are showcased here. Eggs are tiny and difficult to see.
The imported willow leaf beetle was first reported in the United States in 1911 in Staten Island, NY. This invasive insect is native to Europe and prefers willow (Salix spp.) but has also been recorded on poplar (Populus spp.). Common willow hosts include Salix nigra, S. lucida, S. alba, and S. interior. Adults feed on willow leaves by creating irregular notches or holes. Larvae skeletonize leaves. In warmer parts of this insect's introduced range, up to 4 generations per year have been reported. In New England, 2 generations per year are likely. Adults, eggs, and larvae are showcased here on an infested willow in Hampshire County, MA. Pupation has been reported in the literature as occuring on host plant leaves, but that was not observed at this location. When abundant, feeding from the imported willow leaf beetle can cause leaves to brown. Most trees can tolerate total defoliation from this insect, as long as it does not happen every year. Predators and parasites of various life stages of the imported willow leaf beetle are discussed.