Can we accelerate the development of old-growth associates in young forests by thinning or other management techniques?
Many of our young forests are excessively dense and have virtually no undergrowth. Can we do something to these forests to enhance their prospects as habitat for old-growth associated species? Traditional, uniform thinning of already dense forests has relatively subtle effects on lichens and bryophytes (Peterson & McCune 2001a; Rosso et al., 2000a, Thomas et al. 2001). Dense forests rarely have well-developed lower branches (see also Esseen et al. 1996). Even heavy thinning would often do little to create new habitat at the bottom of the vertical profile. But if we expand the concept of thinning to include variable densities and promoting lichen hotspots, then we should be able to make significant contributions to lichen diversity 20 to 50 years from now (Neitlich & McCune 1997; Rolstad et al. 2001). Hotspots are areas with greater than average diversity and abundance of old-growth associates. See “How can we recognize lichen hotspots?” In some cases, structurally heterogeneous young f
