Abstract
Uneven-aged silvicultural approaches are increasingly utilized as efficient management strategies for economic and ecological sustainability of forest resources, including in the southeastern United States where there is interest in converting intensively managed pine plantations to uneven-aged stands. However, success of stand conversion and perpetuation of an uneven-aged forest stand depends on obtaining adequate regeneration of the desired species and its ability to develop into merchantable size classes. In fire-maintained ecosystems, regeneration dynamics can be challenging for species such as slash pine that are not tolerant of fire in the seedling stage. In this study, we examined the survival of slash pine (Pinus elliottii Englm.) regeneration (seedlings and saplings) following prescribed burns in (1) a harvest-created gap (0.4 ha; 70 m diameter) and (2) a mature stand with abundant advanced regeneration at two mesic-hydric flatwoods sites in northwest Florida, USA. We characterized the prescribed burns at the two sites and quantified survival of regeneration of different size classes (<1 m, 1–2 m, 2–3 m, >3 m) at 10 months after the burn. Within the gap, the greatest survival of regeneration was observed at the center (12.5% survival) in comparison to the other positions in the gap (1.92% to 7.14% survival), with all seedlings <3m height killed by the burn. In the stand with advance regeneration, survival ranged between 0% and 50% at different positions, with all regeneration smaller than 2 m killed by fire. Overall, we observed 6.36% and 23.2% survival in the harvest-created gap and the stand with advance regeneration, respectively. Despite these low percent survival values, post-burn slash pine regeneration (seedlings/saplings) density equaled 725 and 4800 per hectare, respectively. Our modeling projections suggest that this level of post-burn regeneration density may be adequate for stand conversion and sustainable uneven-aged silvicultural management of slash pine. These results suggest that seedling size is the preeminent control on slash pine survival after prescribed burn. However, long-term monitoring of stand dynamics following future prescribed burns and cutting cycle harvests will help confirm if slash pine can be sustainably managed using uneven-aged silviculture.
Highlights
Uneven-aged silviculture is increasingly viewed as an appropriate forest management approach to optimize economic and ecological benefits obtained from forests [1,2,3,4,5]
Recent decades have witnessed increasing interest in managing and restoring southern pines species using uneven-aged silvicultural strategies, and simple even-aged plantation stands are being converted to complex uneven-aged structures that rely on natural regeneration [6,7,8]
Advance regeneration above 2 m size in mature slash pine plantation has a fair chance of surviving the prescribed fire and may eventually add a second age class to the stand during conversion
Summary
Uneven-aged silviculture is increasingly viewed as an appropriate forest management approach to optimize economic and ecological benefits obtained from forests [1,2,3,4,5]. The success of such conversions and subsequent application of uneven-aged silviculture in forest stands fundamentally depends on obtaining adequate regeneration after a cutting cycle, which will develop into large size classes and overstory. Regeneration success, survival, and recruitment of pines depend on several factors, including the silvics of the tree species, stand density, site conditions, management, and prescribed fire [17,18,19]. How the prescribed fire and slash pine survival dynamics will play out in a stand with a mature overstory and abundant regeneration of varying sizes is largely unknown, especially in situations when the forest management objective is to transform mature plantations to uneven-aged stand conditions. We used a network of temperature sensors and data loggers installed into slash pine stands to make measurements fire intensity and inventoried pre- and postpine stands make measurements of fire intensity andofinventoried preand post-burn regenerations burn regenerations (seedlings and saplings)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
