Trembling aspen (Populus tremuloides Michx.) regeneration dynamics including sprout production, growth, and clone size were measured to determine the effects of fire on small aspen clone persistence following a mixedseverity wildfire in the Black Hills, South Dakota. Four years postfire, 10 small, isolated aspen clones per low and high fire severity classes were compared with 10 unburned clones. Regardless of severity, fire did not cause an increase in the area occupied by individual aspen clones. Clones affected by high severity fire had the greatest suckering response producing an average of 31 930 sprouts·ha -1 ; more than double the sprout density in unburned clones and 67% greater than the sprout density in clones affected by low severity fire. Sprout growth in high severity clones was 135% and 60% greater than sprout growth in unburned and low severity clones. The succession of these clones to more shade-tolerant ponderosa pine was delayed in clones affected by high severity fire as high severity fire caused significant pine mortality within and surrounding the clone, whereas, without further disturbance, pine encroachment and dominance will likely continue in clones affected by low severity fire.Résumé : La dynamique de régénération du peuplier faux-tremble (Populus tremuloides Michx.), incluant la production de drageons, la croissance et la taille des clones, a été mesurée pour déterminer les effets du feu sur la persistance de petits clones de peuplier à la suite d'un feu dont l'intensité était variable dans les Black Hills du Dakota du Sud. Quatre ans après le feu, 10 petits clones isolés de peuplier pour chacune des classes de sévérité, soit faible soit élevée, ont été comparés à 10 clones non brûlés. Peu importe son intensité, le feu n'a pas causé d'augmentation de la superficie occupée par chacun des clones de peuplier. Les clones affectés par le feu de forte intensité ont produit le plus fort drageonnement avec 31 930·ha -1 , ce qui correspond à plus du double de la densité de drageons dans les clones non brûlés et à 67 % de plus que la densité observée dans les clones affectés par le feu de faible intensité. La croissance des drageons des clones affectés par le feu de forte intensité était respectivement 135 et 60 % plus élevée que celle des clones non brûlés et affectés par le feu de faible intensité. La succession de ces clones vers le pin ponderosa, une espèce plus tolérante à l'ombre, a été retardée dans les clones affectés par le feu de forte intensité qui a causé une mortalité importante du pin à l'intérieur et à la périphérie des clones. Toutefois, si aucune autre perturbation ne survient, l'envahissement et la dominance du pin devraient se poursuivre dans les clones affectés par le feu de faible intensité.[Traduit par la Rédaction] Keyser et al. 2684

We examined the impacts of post-fire salvage logging on regeneration, fuel accumulation, and understorey vegetation and assessed whether the effects of salvage logging differed between stands burned under moderate and high fire severity following the 2000 Jasper Fire in the Black Hills. In unsalvaged sites, fire-related tree mortality created a large standing pool of available fuel, resulting in a rapid increase in surface fuel loads. After 5 years, fine woody debris (FWD) and coarse woody debris (CWD) increased ~1380% and 980% in unsalvaged sites, resulting in FWD and CWD loads of 13 and 25 Mg ha–1, respectively. In contrast, salvage logging limited the rate of accumulation of FWD to ~110% over the same time period and total accumulation of CWD to 16 Mg ha–1. In moderate-severity sites, regeneration was 75% lower in salvaged sites owing to low seed-tree retention, suggesting a re-evaluation of salvage guidelines during future operations in the Black Hills. The likelihood of timely regeneration in high-severity sites, regardless of salvage treatment, is low. We found no discernible effect of salvage logging on understorey development 5 years after fire. Logging caused neither a reduction in total plant cover nor an increase in the abundance of exotic species.

Regenerating oaks (Quercus spp.) has remained a widespread and persistent problem throughout their natural range. Research shows that abundant oak advance reproduction is crucial for success. Although it is recognized that oak advance reproduction accumulation is inversely related to site quality, there has been little effort to model oak advance reproduction density as a function of measured levels of light, water, or nutrient supply. The objective of this study was to determine whether oak advance reproduction could be modeled and mapped with site variables. The study was conducted on the Sinkin Experimental Forest in southeastern Missouri in 20 5-ha experimental units. Vegetation and site data were collected in 120 0.5-ha circular plots with nested subplots for the inventory of the midstory (0.01 ha) and reproduction (0.004 ha). Site variables included soil available water capacity, pH, photosynthetically active radiation in the understory, forest stocking, terrain shape, and slope-aspect. Oak advance reproduction abundance was related to soil acidity and available water capacity and to other site information such as slope-aspect. Models for the red oak group species generally exhibited better fit than those for the white oaks. There also was evidence that estimates of soil acidity and available water capacity can be obtained from the SSURGO database and used in these oak advance reproduction models along with other site information to generate maps of estimated oak reproduction densities. These maps could be used for planning silvicultural interventions to increase the abundance and size of oak advance reproduction before forest regeneration.

In upland forests of the Southern US, management is increasingly focussed on the restoration and maintenance of resilient structures and species compositions, with prescribed burning being the primary tool used to achieve these goals and objectives. In this study, we utilised an extensive dataset comprising 91 burn units and 210 plots across 13 National Park Service lands to examine the relationships between the probability of stem mortality (P(m)) 2 years after prescribed fire and stem size and direct fire effects for 10 common deciduous broadleaved species. Post-fire stem mortality ranged from 6.9% for Quercus alba to 58.9% for Sassafras albidum. The probability of stem mortality was positively associated with maximum bole char height (CHAR) and inversely related to diameter at breast height (DBH) for all 10 deciduous broadleaved species. Model goodness-of-fit varied, with the poorest fit generally associated with firetolerant species and best fit generally associated with fire sensitive species. The information presented contributes to our understanding of post-fire stem mortality and may contribute to the development of fire-related stem mortality models following prescribed burning for eastern tree species. Models should be validated with independent datasets across upland forests types to test for spatial relationships before widespread application.Additional keywords: logistic regression, oak-hickory forests, mixed pine-hardwood forests, post-fire stem mortality. of mesophytic and fire-sensitive species (e.g. Acer rubrum, A. saccharum, Nyssa sylvatica) (Brose et al. 2014). Quantitative data related to the factors associated with species-specific postfire stem mortality in the forests of this region are particularly

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The exclusion of anthropogenic fire is a primary factor responsible for the 'mesophication' of eastern oak (Quercus) forests and resultant oak regeneration problems. Consequently, the reintroduction of fire is increasingly used to promote the establishment and growth of oak and hickory (Carya) and control competition from shade-tolerant species (e.g., red maple (Acer rubrum) in the forest understory. In this study, we examined the effects of fire frequency on the abundance of prominent species in the woody regeneration layer in oak-dominated forests of eastern Kentucky. Treatments included: (1) fire-excluded (FE); (2) frequent fire (FF)five burns over nine years, and (3) less-frequent fire (LFF)two burns over seven years. Prior to burning (2002) and again five and seven growing seasons following the cessation of burning in the FF and LFF treatments (2015), respectively, we inventoried tree species in the woody regeneration layer into three size classes: (1) small seedlings (stems <0.6 m), (2) large seedlings (≥0.6 m and <1.2 m) and (3) small saplings (≥1.2 m and <3.8 cm diameter at breast height). Pre-and postburn, the regeneration layer was dominated by non-oak-hickory species, and although oak-hickory regeneration was abundant the majority of stems were <0.6 m. For oak-hickory, significant treatment effects were limited to the large seedling and small sapling size classes. For large oak-hickory seedlings, density was significantly greater in the LFF than FE treatment. For small oak-hickory saplings, density in the LFF treatment was ~17 and ~4 times greater than in the FE and FF treatments, respectively. This study provides support for the notion that fire-free periods may be more of a factor controlling the abundance and composition of the woody regeneration layer than simply the number of burns. However, despite greater stem density, the fate of the oak-hickory regeneration layer that developed in response to the LFF treatment is uncertain, as the density of non-oak competitors remains high. Additional treatments (e.g., targeted herbicide application, additional burning) may be necessary to reduce the abundance of non-oak species and increase the likelihood of continued recruitment oak-hickory should natural or silvicultural release events occur.

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Forest restoration efforts commonly employ silvicultural methods that alter light and competition to influence species composition. Changes to forest structure and microclimate may adversely affect some taxa (e.g., terrestrial salamanders), but positively affect others (e.g., early successional birds). Salamanders are cited as indicators of ecosystem health because of their sensitivity to forest floor microclimate. We used drift fences with pitfall and funnel traps in a replicated Before-After-Control-Impact design to experimentally assess herpetofaunal community response to initial application of three silvicultural methods proposed to promote oak regeneration: prescribed burning; midstory herbicide; and shelterwood harvests (initial treatment of the shelterwood-burn method) and controls, before and for five years post-treatment. Species richness of all herpetofauna, amphibians, reptiles, frogs, salamanders, or snakes was unaffected by any treatment, but lizard species richness increased in the shelterwood harvest. Capture rate of total salamanders decreased post-harvest in shelterwood units after a 2-3 year delay; Plethodon teyahalee decreased post-harvest in shelterwoods, but also in control units. In contrast, capture rate of total lizards and Plestiodon fasciatus increased in shelterwood stands within the first year post-harvest. Prescribed burn and midstory herbicide treatments did not affect any reptile or amphibian species. A marginally lower proportion of juvenile to adult P. teyahalee, and a higher proportion of juvenile P. fasciatus in shelterwood than control units suggested that heavy canopy removal and associated change in microclimate may differentially affect reproductive success among species. Our study illustrates the importance of longer-term studies to detect potential changes in herpetofaunal communities that may not be immediately apparent after disturbances, and highlights the importance of including multiple taxa for a balanced perspective when weighing impacts of forest management activities.