Effects of Hurricane Isabel on a maturing hardwood forest in the Virginia Coastal Plain1

• Published in: The journal of the Torrey Botanical Society 2008-07, Vol.135 (3), p.360-366
• Main Authors: Prengaman, Kathryn A, Kribel, Jacob R. G, Ware, Stewart
• Format: Article
• Language: English
• Subjects: Coastal plains; Forests; hardwood forest; Hurricane Isabel; Hurricanes; s; Storm damage; Trees; vegetation; wind damage
• ISSN: 1095-5674; 1940-0616
• DOI: 10.3159/08-RA-014.1

When Hurricane Isabel reached the Virginia Coastal Plain on September 18, 2003, it was still a Category 2 hurricane, the strongest hurricane to hit Virginia for more than 70 years, and it inflicted much damage on forests. Permanent hardwood forest plots sampled just months before the storm were re-sampled after the event, revealing an overall damage rate of 14.9% of stems ≥ 2.5 cm dbh, with 7.3% of stems uprooted or secondarily crushed. Larger trees suffered more damage than smaller trees, ranging from 9.7% stems damaged for stems below 10 cm dbh (all by secondary damage) to 32.4% of stems over 60 cm dbh. In the larger size classes, red oaks (predominantly Quercus rubra, but including, Q. falcata, Q. coccinea, Q. velutina) suffered more damage than white oak (Quercus alba). Liriodendron tulipifera and Fagus grandifolia suffered even less damage, but both species lost many branches in an ice storm in 1998, and may have had smaller crowns with less wind resistance than the canopy oaks. There was no significant difference among species in amount of (secondary) damage to smaller trees, although Nyssa sylvatica had a particularly low percent damage. Overall 16% of basal area was lost, but damage was patchily distributed. No basal area was lost in nine of 27 plots, but more than 30% of basal area was lost in seven plots. Loss of large trees created numerous canopy gaps that will no doubt change the forest dynamics in years to come.