European black pine (Pinus nigra Arnold) and Japanese red pine (Pinus densiflora Siebold & Zucc.) are nonnative conifers that have been introduced into the United States and have the ability to hybridize with each other and can potentially become an invasive threat. Interspecific hybridization is an important component of applied genetic tree improvement programs. This study retrospectively examined the influence of climate on interannual growth patterns of 12 full-sib families of hybrid pine that were derived from the hybridization of European black pine and Japanese red pine. The hybrids (Pinus nigra × Pinus densiflora) were initially planted in 1982 in southern mid-Michigan at Michigan State University (MSU) Sandhill Research Area. Tree-ring analysis methods (dendrochronology) were used to quantify the influence of climate (i.e., mean temperature and moisture index) on interannual basal area growth rates of the hybrid pine over an 18 year period (1991–2008). The productivity of the 12 full-sib families of hybrid pine were also projected under future climate change in the 21st century based on the IPCC A1B emission scenario. Climatic sensitivities that were identified in the hybrid pine families included high temperature stress in the summer and fall, moisture stress in the summer, winter harshness, and the timing of the start of the growing season. According to projections, by the end of the 21st century, 8 out of the 12 pine families will show significant decreases in growth outside of the historical norm under the temperature-based dendrochronology models, while 4 families will show significant declines under the moisture index models. The results indicate that the hybrid pine families appear to be generally resilient to future changes in moisture, but will likely be extremely vulnerable to future climatic warming, and thus do not appear to be a future invasive threat. This study represents the first dendrochronological examination of hybrid pine in North America.
INVESTIGATION OF 6-YEAR PLANTATION RESULTS OF TURKISH RED PINE (Pinus brutia Ten.), BLACK PINE (Pinus nigra Arnold subsp. pallasiana) AND TAURUS CEDAR (Cedrus libani A. Rich) SPECIES IN ATATÜRK FOREST FARM
