Cumulative frequency distributions (percent) of snag and nest tree measurements: (a) dbh of old growth snags without cavities (inactive, dotted line), old growth snags with cavities (active ○), and snags in younger stands, 70 (■) and 100 (●) years of age (all inactive; data of [27, 310] for the Coastal Western Hemlock zone); (b) dbh of aspen nest trees in the Cariboo (data of K. Martin); (c) dbh of nest trees used by three species in unmanaged Interior Cedar-Hemlock: red-breasted nuthatch (■), northern flicker (○), and red-naped sapsucker, Sphyrapicus nuchalis (▲) (data of C. Steeger and M. Machmer for the Interior Cedar-Hemlock zone); (d) dbh of nest trees used by red-breasted nuthatches in managed (▲) and unmanaged (○) stands (from [232]: Figure 2).