Seasonal population patterns of the invasive crape myrtle bark scale (Acanthococcus lagerstroemiae) in South Carolina

Crape myrtle bark scale (Acanthococcus lagerstroemiae; CMBS) is an invasive pest that poses a threat to crape myrtles (Lagerstroemia spp.), a popular ornamental species widely used in landscapes across the southern and eastern United States. Since its initial detection in Texas in 2004, CMBS has spread to at least 15 other states across the Southeast. Recent research has investigated CMBS population patterns in parts of the southern US, but we do not have a full picture of these patterns across the entirety of their range. CMBS can negatively impact crape myrtles by facilitating the growth of black sooty mold, which can lead to aesthetic decline and, in extreme cases, plant mortality. In their native range, CMBS can have 2-4 overlapping generations per year, but the life cycle in their introduced range is not fully understood. Here we investigate seasonal patterns and activity peaks of CMBS populations in Clemson and Greenville, South Carolina. To monitor CMBS populations, we placed double sided tape on crape myrtles that were changed approximately every 14 days to identify CMBS activity across different seasons. Our data identifies three activity peaks for crawlers in South Carolina in May, July, and October, suggesting that there are three annual generations. Identifying peak periods for early instar emergence allow us to develop more effective, seasonally timed pest management methods.