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Bug of the Week is written by "The Bug Guy," Michael J. Raupp, Professor of Entomology at the University of Maryland.

A spotted lanternfly is born - Lycorma delicatula

 

Throughout the DMV, wraithlike spotted lanternfly nymphs pop the lid on their egg case and hatch head-first from eggs deposited last autumn by females. They will resume their mischiefs feeding on plants and producing vast amounts of sticky honeydew.

 

Ok, so I thought this was a catchy title but really very few insects give live birth to their young. Aphids and some flies birth living young, however, the vast majority of insects deposit eggs which then hatch, releasing their spawn into the world. Circling back to the topic, last week we received numerous reports of spotted lanternfly eggs hatching in the DMV and in other states nearby. As we learned in a previous episode, invasive Tree of Heaven plays a key role as a food source for spotted lanternfly. Due to its widespread distribution and abundance in Washington County, MD some joke that Tree of Heaven is the titular state tree of Maryland.  To witness the hatching phenomenon of spotted lanternfly, we traveled to a small woodlot near Hagerstown, Maryland. Here scores of Tree of Heaven and several other species were heavily infested with spotted lanternfly. In brilliant morning sunlight we watched dozens of spotted lanternfly nymphs escape the confines of their eggs and transform from ghostly, newly hatched nymphs into bespectacled, black tick-like creatures. Within an hour, highly mobile nymphs made a mad dash upward to the canopy of the tree. On a cherry tree nearby, small herds of black and white polka-dotted nymphs had settled in to suck sap from leaves.  

Watch as spotted lanternfly nymphs hatch from eggs deposited on Tree of Heaven by their mother last autumn. These time-lapse video segments reveal wraithlike nymphs rising from their egg cases over the span of about a half an hour. After hatching, nymphs move away from the mass. Within an hour, their body color changes from creamy white to jet black with pure white spots. They scramble to the tree’s canopy to suck sap from leaves. Nearby, a small herd of slightly older nymphs assemble to feed on vascular elements within a cherry leaf.

The adult spotted lanternfly is a beautiful insect, but nonetheless harmful to many plants.

At this time in the growing season, what can you do if you discover spotted lanternfly nymphs on plants in your landscape or garden? Nymphs are often found feeding on the underside of leaves. By holding a good old red solo cup filled with soapy water (no, not beer) beneath the leaf and tapping the leaf from above, nymphs will take a suicidal leap into the water. It turns out they are not good swimmers. If you don’t mind a more intimate approach to eliminating nymphs, they are easily crushed between fingers if you can catch them. They are really good at hopping away from predators and avenging humans. Another approach, of course, is to use insecticidal sprays. My favorites are those labeled for use in organic food production. These will be gentle on non-target organisms and help conserve them in our gardens and landscapes. Products may include natural pyrethrins, which provide excellent control of nymphs, or insecticidal soaps and oils, including neem oil, that provide good control. Once nymphs have moved from easily accessible low-lying vegetation to upper tree canopies, systemic insecticides may be used to reduce resident populations. We are fortunate to have well-trained arborists and landscapers who can apply highly effective insecticides to control lanternflies on trees and shrubs.  Many web-based information sources recommend scraping eggs masses from trees before they hatch. However, a recent publication by scientists at Penn State indicates that less than 2% of lanternfly egg masses are found in a reachable distance from the ground. They suggest a variety of tactics should be used when dealing with spotted lanternflies.

On the brighter side of this somewhat disturbing invasion is the fact that many of our indigenous beneficial organisms including spiders, praying mantises, and assassin bugs have demonstrated a fondness for snacking on lanternflies. In addition, naturally occurring indigenous fungi infect and kill lanternfly nymphs and adults. Some of these fungi have been formulated to be sprayed on lanternflies and are available commercially. In many locations, Mother Nature’s agents of doom inflict what is known as biotic resistance to these unwelcome invaders, dramatically reducing lanternfly populations. Regional quarantines in several jurisdictions help slow the spread of this clever hitch hiker. As we learn more about managing noisome lanternflies, we can be optimistic that our efforts in partnership with nature’s wisdom will reduce threats imposed by these invaders.    

Acknowledgements

Bug of the Week thanks Josh for finding the location to film spotted lanternflies and a gracious landowner who shared her trees and insects. Paula Shrewsbury provided images and helped wrangle jumpy insects. To learn more about spotted lanternflies, please visit Penn State’s fantastic fact-filled spotted lanternfly website: https://extension.psu.edu/spotted-lanternfly-management-guide Learn more about spotted lanternflies at recent stories on NBCs Today Show and WBALs Sunday Morning Show:

https://www.today.com/video/officials-warn-spotted-lanternflies-are-set-to-return-this-spring-171253317582

https://www.wbaltv.com/article/tips-on-dealing-spotted-lantern-fly-the-bug-guy/43687299

To learn more about regional quarantines in the DMV, please visit these websites:   

https://mda.maryland.gov/plants-pests/Pages/spotted-lantern-fly.aspx

https://www.vdacs.virginia.gov/plant-industry-services-spotted-lanternfly.shtml