http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Matching loblolly pine sources to specific environments
Ring widths during the years 1978 through 1987 were examined and compared for local and nonlocal sources of unimproved loblolly pine (Pinus taeda L.) as well as for two commercially available improved sources. Radial growth and survival were compared and contrasted for the unimproved and improved sources in two separate studies. Local sources were hypothesized to have larger radial growth than nonlocal sources during this period. Of the improved sources, the "superior" source was hypothesized to have larger radial growth during this period, but poorer survival than the drought hardy source. No significant differences in total radial growth were detected among unimproved sources. Total radial growth during the study period did differ significantly by test location. The largest total radial growth occurred at the test location deemed most severe in terms of drought hazard. Reduced stand density resulting from reduced survival was thought to contribute to the large total radial growth. However, correlation among these variables was not significant, providing no support for this hypothesis. No significant differences in total radial growth during the study period were indicated between the two improved loblolly pine types. However, the drought hardy type possessed the larger total radial growth regardless of planting location. No significant differences in total radial growth were observed among the sample tracts. Sample tracts varied tremendously in drought hazard. No significant differences in ring widths were observed among the unimproved or among the improved loblolly pine types during years of extreme drought. However, survival difference between the unimproved loblolly pine types was significant on East Texas sites with high drought potential. Survival of the two improved pine types was comparable among all tracts sampled. Differences in form, however, were readily apparent. The primary objective in this research was the development of modifications for the current planting recommendations for the two improved loblolly pine types in East Texas and the development of planting recommendations for two nonlocal sources of loblolly pine originating from Louisiana...