Cornus florida L. Populations in the Appalachian Ecoregion in Decline
Event Website
http://www.nafew2009.org/
Start Date
6-24-2009 10:50 AM
End Date
6-24-2009 11:10 AM
Description
Over the last three decades a fungal disease identified as Discula destructiva Redlin has severely impacted Cornus florida L. (flowering dogwood) populations throughout its range. This study presents estimates of historical and current C. florida populations across the Appalachian ecoregion and surrounding area in the eastern United States. Population change is calculated at both the county and regional level. Specific objectives were to 1) quantify current C. florida populations in the Appalachian ecoregion, 2) quantify change in C. florida populations for the period beginning in the mid 1980’s to 2006 and 3) identify regional and spatial trends in C. florida population shifts for the same period. Field sampled data were gathered from the USDA Forest Service Forest Inventory and Analysis (FIA) database. Data were assembled from a total of 41 FIA units in 13 states for county-level estimates of the total number of all live trees for C. florida on timberland within its natural range. Analysis of covariance, comparing historical and current county-level dogwood population estimates with average change in forest density as the covariate, was used to identify significant changes within regional (FIA) units. Results indicate that significant (P < 0.05) regional (FIA unit) declines were observed in 33 of the 41 (80 percent) sampled regional units. Although, declines were widespread throughout all of the regional units surrounding the Appalachians, the largest declines appeared to be centered within the Appalachian Mountains. These results indicate that an important component of the eastern deciduous forest appears to be in serious decline throughout the Appalachians. Furthermore, these results support localized empirical results and landscape scale anecdotal evidence.
Cornus florida L. Populations in the Appalachian Ecoregion in Decline
Over the last three decades a fungal disease identified as Discula destructiva Redlin has severely impacted Cornus florida L. (flowering dogwood) populations throughout its range. This study presents estimates of historical and current C. florida populations across the Appalachian ecoregion and surrounding area in the eastern United States. Population change is calculated at both the county and regional level. Specific objectives were to 1) quantify current C. florida populations in the Appalachian ecoregion, 2) quantify change in C. florida populations for the period beginning in the mid 1980’s to 2006 and 3) identify regional and spatial trends in C. florida population shifts for the same period. Field sampled data were gathered from the USDA Forest Service Forest Inventory and Analysis (FIA) database. Data were assembled from a total of 41 FIA units in 13 states for county-level estimates of the total number of all live trees for C. florida on timberland within its natural range. Analysis of covariance, comparing historical and current county-level dogwood population estimates with average change in forest density as the covariate, was used to identify significant changes within regional (FIA) units. Results indicate that significant (P < 0.05) regional (FIA unit) declines were observed in 33 of the 41 (80 percent) sampled regional units. Although, declines were widespread throughout all of the regional units surrounding the Appalachians, the largest declines appeared to be centered within the Appalachian Mountains. These results indicate that an important component of the eastern deciduous forest appears to be in serious decline throughout the Appalachians. Furthermore, these results support localized empirical results and landscape scale anecdotal evidence.
https://digitalcommons.usu.edu/nafecology/sessions/disease/3