Lambdin, P.L., Grant, J., & Reardon, R.C. 2008 Density and distribution of the elongate hemlock scale on eastern hemlock in the southern Appalachians.. Proceedings of the XI International Symposium on Scale Insect Studies, Oeiras, Portugal, 24-27 September 2007. ISA Press Lisbon, Portugal 322 pp.

Notes: The density ratio of the elongate hemlock scale, Fiorinia externa, infesting eastern hemlock trees at the two urban and two forest sites ranged from 3.5 to 3.9 inferring a heavy population at each site. No significant genetic differences among elongate hemlock seal populations from Massachusetts, North Carolina and Tennessee were inferred using PCR procedures. Although up to 12 live and dead elongate hemlock scale specimens were observed on the Underside of the needles, the average number of specimens per needle ranged from 1.92 at the Lynnhurst urban site to 3.42 at the U. S. Forest Service urban site The average number of live specimens ranged from 0.45 specimens per needle at Biltmore forest site to 0.74 specimens per needle at the US Forest Service headquarters _ urban site. The number of specimens per needle was Significantly lower at the Biltmor Forest site compared to the numbers recorded at the urban sites. The mean percentage live elongate hemlock scales in the populations ranged from 20% at Biltmore forest site t 31 % at the Lynnhurst urban site. The annual mean number of elongate hemlock seal consistently declined over the evaluation period, from 2.97 specimens per needle in 20 _ to 2.13 in 2006. This decline was due in part to the consistent increase of natural enemies within the infested sites.