Disturbance History and Serotiny of Pinus contorta in Western Montana

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. This content downloaded from 128.235.251.160 on Sun, Abstract. Mature Pinus contorta var. latifolia in the Bitterroot watershed of western Montana bear either predominantly serotinous cones (cone scales sealed by a resin bond and requiring a heat treatment for opening) or nonserotinous cones. This study investigated the extent to which amongstand variation in serotiny could be explained by environmental variables, estimated fire frequency, and the nature of the stand-initiating disturbance. The frequency distribution of serotiny at the stand level was bimodal, with peaks near 25 and 75% serotinous cones. Stand-level serotiny was not related to measured environmental variables and was only weakly related to estimated fire frequency. In contrast, much of the among-stand variation in serotiny could be explained by the nature of the standinitiating disturbance, with a predominance of serotinous trees in stands that had originated from stand-replacing burs and of nonserotinous trees in those that had originated from disturbances not related to fire. The disturbance regime is highly variable in time and space, and this variability, coupled with gene flow, is an important factor maintaining the polymorphism of cone type in stands.

Conflicting selection from fire and seed predation drives fine-scaled phenotypic variation in a widespread North American conifer

“…Muir and Lotan (47) found that the frequency of serotiny in lodgepole pine was most strongly related to the type of disturbance that initiated a stand, with fire-initiated stands being much more serotinous than other stands. This suggests the potential for very rapid change in the frequency of serotiny (i.e., a single fire interval), and that high frequencies of stand-replacing fire should result in high frequencies of serotiny (because most stands will have initiated due to a stand-replacing fire).…”

Making the case for cumulative impacts assessment: Modelling the potential impacts of climate change, harvesting, oil and gas, and fire

“…9). The sub-model is based on previously published principles and equations (Muir and Lotan 1985, Greene and Johnson 1994, 1998Gauthier et al 1996, Charron and Greene 2002, Calogeropoulos et al 2003, Radeloff et al 2003 and is applied to determine both in situ (from propagules that come from the cell itself) and ex situ (from propagules that come from neighbouring cells) regeneration. Modifications were brought to these equation systems based on the work of Hogg and Schwartz (1997), in order to take GCC into account.…”

Wildland fire in ecosystems: effects of fire on flora

“…2-12), and geographically. A high degree of cone serotiny is likely to occur where there are large, stand-replacement fires; relatively short, fire-free intervals; and fire sizes large enough to limit seed dispersal from unburned areas (Muir and Lotan 1985;Parker and Kelly 1989).…”