Date of Graduation


Document Type


Degree Name

Master of Science in Entomology (MS)

Degree Level





Frederick M. Stephen

Committee Member

Ashley P. Dowling

Second Committee Member

Kimberly G. Smith


Biological sciences, Distribution, Flight activity, Monochamus, Monochamus carolinensis, Monochamus titillator, Seasonal activity


Monochamus (Coleoptera: Cerambycidae) are a genus of longhorn beetles commonly known as pine sawyers. They have a worldwide distribution coincident with pines (Pinaceae) and are vectors of the pinewood nematode (Bursaphelenchus xylophilus). In the United States, there are eight known Monochamus species and they have a sympatric distribution with at least one other Monochamus species throughout their range. Monochamus are known to attack stressed, dead, and dying conifers especially pines. In the Ozark- St. Francis National Forest in Arkansas, there are two species of pine sawyers and they share this sympatric distribution observed throughout the United States, M. titillator (southern pine sawyer) and M. carolinensis (Carolina sawyer). Both species seem to occupy the same ecological niche – similar seasonal flight patterns, life history, and host material. The objectives of this study were to determine diurnal or nocturnal height flight patterns of M. titillator and M. carolinensis, compare heights at which Monochamus fly, and examine within tree distribution of oviposition pits and emergence densities of both species using suspended shortleaf pine (Pinus echinata) bolts. From these objectives we were able to determine Monochamus were active at night (6 PM – 6 AM), and were more often captured at the base of canopy than at breast height. There were no differences between species by diurnal or nocturnal height flight patterns. During colonization of suspended pine bolts there was a higher density of oviposition pits in the base of canopy than at breast height. There were no differences in the density of emerging Monochamus by height at which bolts were suspended. The majority of Monochamus emergence from suspended bolts was M. titillator. These studies confirmed diurnal and height flight patterns, within tree distribution, and emergence densities of Monochamus species in the Ozark St. Francis National Forest in Arkansas. However, my studies failed to elicit ecological differences between M. titillator and M. carolinensis. Understanding the biology and ecology of Monochamus species may allow refinement of trapping methods, as well as better understanding of how Monochamus species interact among each other.