Assessing the effects of mowing intensity on the overwintering stem-dwelling insect community of Solidago altissima L. (Asterales: Asteraceae)

Abstract

Mowing is a commonly used and necessary practice in the management of urban meadowscapes. However, mowing is also a source of mortality for insects in these meadowscapes. In this study, we examined how changes in mowing intensity for mows performed in late fall affect overwintering stem-dwelling insects. We define mowing intensity as the size of thatch produced by the selected mowing equipment and blade positioning. We also generate more information on the spatial structure of the stem-dwelling insect community in these urban meadowscapes, both within individual stems and within the broader habitat. We artificially simulated different levels of mowing intensity on the stem-dwelling insects of Solidago altissima L. (Asterales: Asteraceae) by cutting stems to different lengths and recorded their survival and mortality outcomes. We found that a low intensity mowing treatment yielded lower mortality rates than a no-mow control and a high intensity mowing treatment. We also found that stem-dwelling insects are distributed in a non-random arrangement vertically within stems of Solidago altissima and in the broader urban meadowscape. These findings highlight the importance of understanding the effects of changing mowing parameters on the insect community when designing management practices for urban meadowscapes. We also identify some new gaps in our understanding of stem-dwelling insects and how they may interact with disturbances.