Treesearch

The Proceedings reports the results of a workshop focusing on the topic of bark beetle genetics. The workshop evolved because of the growing interest in this relatively unexplored area of bark beetle research. Workshop participants submitted brief descriptions of their views of the current status of bark beetle genetic research and needs for the future. Contributions vary from broad overviews to detailed descriptions of specific projects. A common theme is the potential for rapid advances in this area of research given recent technological advances in the field of genetics. Also included...

A model is presented that simulates the effects of streamflow and sediment transport on survival of salmonid embryos incubating in spawning gravels in a natural channel. Components of the model include a 6-yr streamflow record, an empirical bed load-transport function, a relation between transport and infiltration of sandy bedload into a gravel bed, effects of fine-sediment infiltration on gravel properties, and functions relating embryo survival to gravel properties.

Soil and cambium temperatures must be known to ascertain certain effects of prescribed fires on trees. Thermocouple-based systems were devised for measuring soil and cambium temperatures during prescribed fires. The systems, which incorporate both commercially available and custom components, perform three basic functions: data collection, data retrieval, and data translation. Although the systems and procedures for using them were designed for research purposes, they could be adapted for monitoring operational prescribed fires.

Genetic diversity in sugar plne will be severely reduced by the blister rust pandemic predicted within the next 50 to 75 years. We model effects of the epidemic on genetic diversity at the stand and landscape levels for both natural and artificial regeneration. In natural stands, because natural frequencies of the dominant gene (R) for resistance are low, the most obvious effect on sugar pine will be demographic, with a crash in population size expected following disease onset. Many stands in areas of lowest R frequency may lose the allele during the initial epidemic and go extinct. In...