The effects of post-wildfire salvage logging on plant reproductive success and pollination in Symphoricarpos albus, a fire-tolerant shrub

Abstract Post-wildfire salvage logging is an increasingly used land management tool with poorly understood ecological consequences for understory flowering plants and their interactions with pollinators. Understanding these consequences of salvage logging is important because an essential aspect of post-wildfire forest succession involves pollination and plant reproduction. For snowberry (Symphoricarpos albus), an ecologically-important and fire-tolerant shrub, we tested the long-term effects of post-wildfire logging on plant reproduction and pollen limitation using a supplemental-pollen experiment coupled with pollinator observations of S. albus and of potential co-flowering competitors of S. albus. Nearly a quarter century after these disturbances, we found no effects of post-wildfire logging on the reproduction of naturally-pollinated plants. The reproduction of some S. albus individuals were pollen limited, but only in unlogged areas, suggesting that plants in unlogged areas have higher potential reproduction compared to those logged areas but are unable to achieve this higher level of reproduction due to lack of pollination. This pollen limitation of S. albus reproduction is consistent with the relatively high floral densities of potential competitors of S. albus and generally low pollinator visitation rates in unlogged areas. Together, these results suggest that legacies of post-wildfire logging may restrict the reproductive potential of this shrub for at least several decades after the logging is complete, but this restriction is likely due to altered abiotic conditions and not via lack of pollination.

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