Beech bark disease: spatial patterns of thicket formation and disease spread in an aftermath forest in the northeastern United States

• Published in: Canadian journal of forest research Vol. 44; no. 9; pp. 1042 - 1050
• Main Authors: Giencke, Lisa M, Martin Dovčiak, Giorgos Mountrakis, Jonathan A. Cale, Myron J. Mitchell
• Format: Journal Article
• Language: English
• Published: Ottawa NRC Research Press 01.09.2014; Canadian Science Publishing NRC Research Press
• Subjects: Acer saccharum subsp. saccharum; Adirondack Mountains; Adirondacks; Agricultural research; American beech; analyse bidimensionnelle de semis de points; Bark; BBD; Beech; beech thickets; bivariate point pattern analysis; Canopies; canopy; disease severity; Disease spread; Disease transmission; Diseases and pests; Fagus grandifolia; Forest management; Forestry; fourrés de hêtre; Geography; hardwood forests; hêtre d’Amérique; landscapes; maladie corticale du hêtre; mortality; Mountains; Plant diseases; Plant-pathogen relationships; saplings; Trees; New York; Adirondacks; United States; United States > US
• ISSN: 1208-6037; 0045-5067; 1208-6037
• DOI: 10.1139/cjfr-2014-0038

Beech bark disease (BBD) has affected the composition, structure, and function of forests containing a significant proportion of American beech (Fagus grandifolia Ehrh.) across North America. BBD spread has been investigated at landscape and regional scales, but few studies have examined spatial patterns of disease severity and spread within stands where forest management mitigation measures can be implemented. We analyzed changes in forest composition between 1985 and 2009 and fine-scale spatial patterns of BBD between 2000 and 2009 in a ∼2 ha northern hardwood stand in the Adirondack Mountains of New York using location and disease severity of beech trees. A bivariate point pattern analysis was implemented to examine spatial patterns of beech thicket formation and BBD spread to beech saplings. Abundance of beech saplings increased near highly diseased canopy beech trees and around dead beech and sugar maple (Acersaccharum Marsh.). Disease severity of beech saplings was highest in close proximity to highly cankered canopy beech trees. Thus, BBD leads to the formation of beech thickets, and thickets are often located where saplings are most likely to become infected, increasing the likelihood that secondary killing fronts will develop and lead to heavy BBD-induced mortality in aftermath northern hardwood forests of North America.