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Flight and emergence of the redbay ambrosia beetle, Xyleborus glabratus Eichhoff, were monitored from March 2011 through August 2012 using Lindgren funnel traps baited with manuka oil and emergence traps attached over individual beetle galleries on infested redbay (Persea borbonia (L.) Sprengel) trees. Of the 432 gallery entrances covered with emergence traps, 235 (54.4%) successfully produced at least two adults. Gallery success rates and time until adult emergence were highly variable and strongly depended on time of year galleries were initiated. Successful galleries produced 23.4 ± 2.50 (x ± SE) adult X. glabratus but one had 316 adults emerge from it. Galleries were active for an average of 231.9 ± 6.13 d but five were active for over 1 yr and one gallery produced beetles for 497 d. In total, 5,345 female and 196 males were collected during the study resulting in a sex ratio of ~27:1 (female:male) emerging from galleries. Ambrosia beetles other than X. glabratus were recovered from 18 galleries or ~4% of those studied. Beetles that attacked larger diameter trees were more likely to be successful and produce more brood. Lindgren trap captures reflected emergence trap collections but with a delay of about 1 mo between peaks in emergence and capture in traps. Peaks of activity occurred in fall 2011 and spring 2012, but at least some adult beetles were collected using both methods in every month of the year.

Fine mesh screen was used to create a physical barrier to prevent redbay ambrosia beetles, Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae), from accessing various parts of the boles of redbay trees, Persea borbonia (L.) Sprengel, and infecting them with the laurel wilt fungus, Raffaelea lauricola (T.C. Harrington, Fraedrich, & Aghayeva). Screen barriers prevented beetles from attacking boles of mature redbay trees from the ground to 1 or to 3 m and from 1 to 3 m above ground. Untreated control trees were sampled more extensively to determine how location of initial attacks varied with height, diameter, and moisture content of the wood. Screening did not affect tree survival, and all of the trees died within 243 d from the beginning of observation. Initial points of attack by X. glabratus varied from ground level to heights of at least 6.6 m. Trees showed characteristic laurel wilt symptoms with as few as two X. glabratus entry points. The number of attacks exhibited nonlinear relationships with diameter (P = 0.0004; r2 = 0.82) and height (P = 0.0013; r2 = 0.69) but were not correlated with moisture content. Attacks increased gradually with increasing stem diameter up to approximately 10 cm after which the attacks became more numerous. X. glabratus attacks were most numerous on the tree bole near the ground. Attacks then declined as tree height reached 2-3 m. From 3 to 8 m, attacks were relatively consistent.

Redbay ambrosia beetle, Xyleborus glabratus Eichoff, is an exotic species to North America vectoring a deadly vascular wilt disease of redbay [Persea borbonia (L.) Spreng], swampbay [P. palustris (Raf.) Sarg.], avocado (P. americana Mill.), and sassafras [Sassafras albidum (Nutt.) Nees]. Xyleborus glabratus is attracted to manuka oil lures, which are commercially available, and phoebe oil. Variable efficacy of manuka oil lures and insufficient availability of phoebe oil prompted us to investigate the reasons behind changes in manuka oil lure efficacy and to test cubeb oil, a readily available essential oil from Piper cubeba L. seeds, as an alternative attractant. Attraction, release rates and durations, and volatile composition of manuka oil lures manufactured in 2008 were compared with manuka oil lures manufactured in 2012, and to whole and a distilled fraction of cubeb oil. Manuka oil lures from 2008 were more attractive to X. glabratus than controls for 8 wk, whereas lures from 2012 were attractive for only 2 wk. Cubeb oil and the distilled fraction of it were as attractive as or more attractive than manuka oil in three trials. In gravimetric studies, manuka oil lures from 2008 and cubeb oil lures continued to release volatiles for 57 d, whereas lures from 2012 stopped after 16 d. The chemical composition of volatiles released from new manuka oil lures from 2008 was similar to 2012; however, a preservative (butylated hydroxytoluene) was detected in the 2008 lures. Cubeb oil was an effective attractant for X. glabratus that lasted 8-9 wk when released from bubble lures.

The bean plataspid, Megacopta cribraria (F.), recently was discovered in the United States feeding on kudzu, Pueraria montana Lour. (Merr.) variety lobata (Willd.), an economically important invasive vine. We studied its biology on kudzu and its impact on kudzu growth. We also tested its ability to use other common forest legumes for oviposition and development. Flight intercept traps operated from 17 May 2010 to 31 May 2011 in a kudzu field near Athens, GA showed three peaks of adult flight activity suggesting there are two generations per year on kudzu. Vine samples examined for eggs from April 2010 to April 2011 and June to October 2011 showed two periods of oviposition activity in 2010, which coincided with the peaks in adult activity. In 2011, the second period of oviposition began on or before 24 June and then egg abundance declined gradually thereafter until late August when we recovered <2 eggs/0.5 m of vine. Samples of the five nymphal instars and adults on vines did not show similar trends in abundance. Adults did not lay eggs on the various legume species tested in 2010 in a no-choice test possibly because the cages were too small. In the 2011 field host range experiments conducted in a kudzu field by using 12 legume species, M. cribraria preferentially oviposited on kudzu over soybean, Glycine max Merrill., but they still laid 320 eggs per plant on soybean. Lespedeza hirta (L.) Hornem. and Lespedeza cuneata (Dum. Cours.) G. Don had 122.2 and 108.4 eggs per plant, respectively. Kudzu and soybean were the only species M. cribraria completed development on. Plots protected from M. cribraria feeding by biweekly insecticide applications had 32.8% more kudzu biomass than unprotected plots. Our results show that M. cribraria has a significant impact on kudzu growth and could help suppress this pest weed.