Beech bark disease in Michigan: Spread of the advancing front and stand-level impacts
| Authors: | Deborah G. McCullough, James B. Wieferich. |
| Year: | 2015 |
| Type: | Book Chapter |
| Station: | Washington Office |
| Source: | Potter, K.M., and B.L. Conkling, editors. 2015. Forest Health Monitoring: National Status, Trends and Analysis, 2014. General Technical Report SRS-209. Asheville, North Carolina: U.S. Department of Agriculture, Forest Service, Southern Research Station. 190 p. |
Abstract
Beech bark disease (BBD) has spread across roughly half of the range of American beech (Fagus grandifolia) in North America since it was introduced into Nova Scotia around 1890 (Erlich 1932, 1934; Gwiazdowski and others 2006; Houston 1994). The nonindigenous beech scale insect, Cryptococcus fagisuga Lind., mediates BBD by piercing the outer bark of beech trees, facilitating entry of the nonindigenous fungi Neonectria faginata, which colonizes only Fagusspp., or Neonectria ditissima (synonymous with N. galligena), which occurs on a variety of hardwood species in North America and Europe (Castlebury and others 2006, Houston and O’Brien 1983). The fungi kill small patches of phloem and cambium, and as dead tissues coalesce, large branches and the trunk are girdled (Burns and Houston 1987, Ehrlich 1934). Terms used to depict the three stages of BBD include the “advancing front” where trees are infested by beech scale, the “killing front” where trees are dying from fungal infection, followed by the “aftermath forest” characterized by beech mortality, infected “cull” trees, and, often, dense thickets of beech sprouts (Houston 1994, Houston and O’Brien 1983, Sh igo 1972).