By David Coyle, Ph.D.
Formed into hedges, balls, cylinders, and another form possible, boxwoods (species within the genus Buxus) are among the most ubiquitous and hearty panorama shrubs round. So many boxwood bushes are planted in landscapes that you just won’t even discover them—till these darkish inexperienced, compact crops are gone, in fact. Then folks discover.
One of many largest threats to boxwoods is Cydalima perspectalis, colloquially known as the field tree moth. A number of colleagues and I evaluate the biology and administration of C. perspectalis in a new article printed this week within the open-access Journal of Built-in Pest Administration. This pest, native to jap Asia, has been making its manner throughout the globe through unintended introductions, doubtless on panorama crops. It has been consuming Buxus and different species all through Europe and most just lately North America, the place it was found close to Toronto, Ontario, in summer season 2018.
As soon as Canadian regulatory officers found this infestation (with the assistance of citizen science—it was reported on iNaturalist!), they launched a complete and efficient monitoring and administration program. As C. perspectalis adults seem much like different native moth species, correct identification is crucial. The larvae, nonetheless, are fairly distinct in that they devour boxwood foliage and depart webbing on the leaves. Excessive populations can strip boxwoods to the leaf veins and trigger plant mortality. With a number of generations per yr, these caterpillars can actually wreak havoc on a boxwood planting.
In summer season 2021, crops infested with C. perspectalis have been present in a number of states within the U.S., together with New York, Michigan, Connecticut, and South Carolina. Regulatory motion was instantly taken, and as of September 2022 no established populations of C. perspectalis are identified. The truth that introductions to a number of states resulted in no identified infestations is a testomony to the regulatory officers in these states.
In the end, correct and correct scouting and prevention is one of the best protection in opposition to this pest. Administration may be difficult, however pheromone lures do exist and a few efficient chemical administration strategies can be found. We all know little about organic management choices at this level, although a number of pure enemies will assault this pest.
Whereas the story of C. perspectalis is much from over, there may be cause to be optimistic. It is a nice instance of how citizen science— folks reporting issues they see— may also help uncover a brand new pest. That is additionally an important instance of how briskly and thorough regulatory motion may be efficient in stopping an infestation. And with as a lot boxwood as we have now throughout the panorama (and the affect it has on the horticultural trade), we’ll all profit from maintaining this pest out of the U.S.