The title compound, also known as isopimaric acid, C(20)H(30)O(2), was isolated from slash pine rosin. There are two unique mol-ecules in the unit cell. The two cyclo-hexane rings have classical chair conformations. The cyclo-hexene ring represents a semi-chair. The mol-ecular conformation is stabilized by weak intra-molecular C-H⋯O hydrogen-bonding inter-actions. The mol-ecules are dimerized t...

The relationship between quadratic mean diameter and tree density appeared curvilinear on a log-log scale, based on data from direct-seeded slash pine (Pinus elliottii var. elliottii Engelm.) stands. The self-thinning trajectory followed a straight line for high tree density levels and then turned away from this line as tree density decreased. A system of equations was developed to model the re...

The fruit of woody plants is important as food for wildlife (Martin et al. 1951, Lay 1965). The relation of fruit production to southern forest stand conditions has been explored in only a few studies. Fruit production is greater in forest clearings than in closed forest stands (Lay 1966, Elalls and Alcaniz 1968). In Georgia slash pine (Pinus elliottii) plantations, fruit yields of shrubs are g...

Photochemical quenching, nonphotochemical quenching, and yield of photosystem II were measured on seedlings of full-sibling, open-, and self-pollinated slash pine (Pinus elliottii Engelm. var. elliottii) families. Our results reveal that genetic variation in photochemical quenching and yield of photosystem II exists within this species. The pattern of variation found in these traits is consiste...