Predicting Survival of East Texas Loblolly and Slash Pine Plantations Infected with Fusiform Rust

摘要

Repeated measurement during 1982-1992 of East Texas Pine Plantation Research Project permanent plots in loblolly( Pinus taedaL .) and slash( Pinus elliottii Engelm.) pine plantations throughout East Texas were used to develop equations for predicting the future number of trees per acre. A typical condition of East Texas pine plantations is the incidence of fusiform rust( Cronatrium quercuum [Berk.] Miyabe ex Shirai f. sp. fusiforme). A regression procedure for fitting nonlinear systems of equations was used to fit survival models that considered the possibility that trees with no rust galls on the stem could either (1) remain uninfected and alive, (2) become infected yet still alive or (3) die. For infected stem so, only two possible outcomes were considered in the model:(1) remain infected and alive or (2) die.Analyses of the differences between predicted and observed values indicated no adverse trends for either of the two species. Apparently the models do represent observed survival patterns.South J. Appl. For. 20(1):30-35.