Standing dead trees, or snags, are natural components of forest stands and
are important habitats for many wildlife species. We examined snag dynamics
from 1982-1990 on 140 0.1 ha plots in the upper Piedmont of South Carolina
. Plots were established in 10 stand type-age class combinations. Mean snag
density was 28.4 snags/ha and mean snag diameter (DBH) and height were 20.
3 cm and 9.9 m, respectively. Highest snag densities occurred in hardwood s
tand types; pine plantations had lower (p less than or equal to 0.05) snag
density than all other types. Within a particular stand type, snag densitie
s, recruitment rates, and loss rates generally were lowest in the oldest ag
e classes. Intermediate age classes of all stand types had higher snag dens
ities and snag turnover rates than younger or older stands within that type
. Young pine plantations had the lowest recruitment rate ((x) over bar=1.79
snags/ha/year) and old pine plantations had the lowest loss rate ((x) over
bar=1.59 snags/ha/year) of all the stand type-age class combinations. Alth
ough twenty species of snags were observed, five species/species groups, sh
ortleaf pine (Pinus echinata), red oaks (Quercus spp.), white oaks (Quercus
spp.), loblolly pine (P. taeda), and yellow poplar (Liriodendron tulipifer
a), occurred most frequently. Snag DBH and cavities/snag were not significa
ntly correlated. Stage of decay for cavity and noncavity snags (r=0.97 and
0.83, respectively; p less than or equal to 0.05) and number of cavities/sn
ag (r=0.78) increased with year since snag recruitment. Ten snag species co
ntained cavities ((x) over bar=0.1 cavities/snag), but shortleaf pine accou
nted for 56% of the cavity years observed ((x) over bar=0.18 cavities/snag)
. Three other softwood species also contained equal to or above average num
bers of cavities/snag. Approximately 30% of all snags fell within two years
of recruitment, 55% within three years, and 95% within six years. Snag lon
gevity was independent of diameter class (p=0.67). Hardwood snags, especial
ly those in upland hardwood stands, appeared to persist longer than pine sn
ags. As pine plantations managed on short rotations (<25 years) and older-a
ged stands (>50 years) of all types may not provide abundant snags in the S
outh Carolina Piedmont, the potential for wildlife habitat might be enhance
d if older, larger diameter trees, especially softwood species, are retaine
d or designated as snag replacements. (C) 1999 Elsevier Science B.V. All ri
ghts reserved.