Effects of thinning and prescribed fire frequency on ground flora in mixed Pinus-hardwood stands

Barefoot, Carson R.; Willson, Kevin G.; Hart, Justin L.; Schweitzer, Callie J.; Dey, Daniel C.

doi:10.1016/j.foreco.2018.09.055

Cited by 29 publications

(36 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…and Carex spp.). In our results, increases of absolute cover and IV were mostly found in MB treatments, suggesting that additive effects of M and B on basal area reduction provides sufficient light availability for graminoid regeneration [13,64]. However, there was low abundance of graminoids throughout all treatments, which may be the result of dispersal limitations.…”

Section: Graminoidsmentioning

confidence: 50%

“…While our findings showed that total forb cover and IV did not significantly change from 2001 to 2016, we observed significant increases of nitrogen-fixing forb cover over time. Other studies reported that the most significant increases occurred following more intensive treatments [32,47,60,64,71]. Reductions in overstory basal area, like those reported by Waldrop et al (2016), create more available space and sunlight, which in turn promotes the growth of forbs, especially light-demanding nitrogen-fixers.…”

Section: Forbsmentioning

confidence: 92%

“…They also reported that burning stimulated growth of these species, but insufficient light availability reduced seedling abundance over time [58,59]. In addition, these smaller mesic hardwood saplings are likely the most susceptible to fire-related mortality, as their bark is not fully-developed and the flames are in closer proximity to their leaves and buds than that of taller individuals [64].…”

Section: Mesic Hardwoodsmentioning

confidence: 99%

See 2 more Smart Citations

Understory Vegetation Responses to 15 Years of Repeated Fuel Reduction Treatments in the Southern Appalachian Mountains, USA

Oakman

Hagan

Waldrop

et al. 2019

Forests

View full text Add to dashboard Cite

Decades of fire exclusion in the Southern Appalachian Mountains led to fuel accumulation and conversion from open oak-pine woodlands to closed-canopy mesic forests dominated by shade-tolerant hardwoods and shrubs that often do not support a diverse understory. Southern Appalachian forest managers and scientists recognize this and are implementing silvicultural treatments such as prescribed burning, mechanical treatments or a combination of these to restore forest structure. In this study, conducted at the Southern Appalachian Fire and Fire Surrogate Study site in Green River Game Land, North Carolina, we assessed the effects of four fuel reduction methods: burned 4x (B), mechanical treatment 2x (M), mechanical treatment 2x + burned 4x (MB), and control (C) on the changes in understory vegetation guilds from pretreatment to post-treatment years (2001–2016). The MB treatment was most effective at meeting the restoration objectives, as it resulted in increases in oak (ΔMB = 23,400 stems/ha) and pine (ΔMB = 900 stems/ha) stem density, importance value - calculated as the sum of relative cover and frequency - for graminoids (ΔMB = 26.0), and density of oak stems >50 cm in height (ΔMB = 7133 stems/ha). The B and M treatments were generally less effective, but nonetheless met a subset of the restoration objectives. The B treatment reduced ericaceous shrub cover (ΔB = −1.2%) and increased oak stems 10–50 cm in height (ΔB = 10,017 stems/ha), while the M treatment resulted in only modest increases of mesic hardwoods, specifically for yellow-poplar (ΔM = 200 stems/ha) and blackgum (ΔM = 200 stems/ha) as compared with other treatments, but significantly increased mountain laurel and rhododendron cover (ΔM = 10.0%). Overall, these fire and fire surrogate treatments had some success in restoring understory structure, but our findings suggest a slow response in understory herbaceous vegetation.

show abstract

Section: Graminoidsmentioning

confidence: 50%

Section: Forbsmentioning

confidence: 92%

Section: Mesic Hardwoodsmentioning

confidence: 99%

See 1 more Smart Citation

Understory Vegetation Responses to 15 Years of Repeated Fuel Reduction Treatments in the Southern Appalachian Mountains, USA

Oakman

Hagan

Waldrop

et al. 2019

Forests

View full text Add to dashboard Cite

show abstract

“…Disturbances are prevalent in all natural ecosystems, and integral for the maintenance of biodiversity [23,24]; however, anthropogenic alterations of these disturbance regimes (i.e., frequency, intensity, and type of disturbance) pose global threats to biodiversity [25]. Different disturbance regimes reinitiate forest stands and trigger resource reallocation [26][27][28][29][30][31]. As such, studying the patterns of understorey vegetation following various disturbance regimes may assist with clarifying how understorey vegetation responds to particular disturbances, toward improving the conservation of biodiversity in the context of dramatic declines in biodiversity worldwide [32].…”

Section: Colonization Timementioning

confidence: 99%

“…Regardless of which types of forest management practices are adopted, the lack of sufficient time for colonization will reduce the abundance and diversity of understorey vegetation, as species with low dispersal capacities require a long time to colonize into newly available spaces and tap into resources following disturbances [16,121]. In the interim, clearcutting and partial harvesting are likely to modify the abundance and diversity of understorey vegetation by altering the understorey resource availability and heterogeneity [23,30,118,[124][125][126][127]. In contrast to stand-replacing wildfire that eradicates both overstorey and understorey vegetation, and releases soil nutrients through the combustion of coarse woody debris [15,69,118,120], clearcutting, which also removes overstorey vegetation, has a lesser impact on understorey vegetation [14,33,123].…”

Section: The Effects Of Forest Management Practices (Clearcutting Andmentioning

confidence: 99%

Forest Understorey Vegetation: Colonization and the Availability and Heterogeneity of Resources

Wang

Huang

et al. 2019

Forests

View full text Add to dashboard Cite

Understorey vegetation comprises a major portion of plant diversity and contributes greatly to nutrient cycling and energy flow. This review examines the mechanisms involved in the response of understorey vegetation to stand development and the overstorey canopy following disturbances. The overall abundance and diversity of the understorey is enhanced with the availability and heterogeneity of light, soil nutrients, soil moisture, and substrates. Vascular plants are positively impacted by the availability and heterogeneity of light and soil nutrients, whereas non-vascular vegetation is more strongly influenced by colonization time, soil moisture, and substrates, and is decreased with a higher proportion of broadleaf overstorey. The availability of resources is a prominent driver toward the abundance and diversity of understorey vegetation, from the stand initiation to stem exclusion stage under a single-species dominated overstorey. However, resource heterogeneity dominates at the later stages of succession under a mixed overstorey. Climate and site conditions modify resource availability and heterogeneity in the understorey layer, but the extent of their influences requires more investigation. Forest management practices (clearcutting and partial harvesting) tend to increase light availability and heterogeneity, which facilitates the abundance and diversity of understorey vascular plants; however, these factors reduce the occurrence of non-vascular plants. Nevertheless, in the landscape context, anthropogenic disturbances homogenize environmental conditions and reduce beta-diversity, as well, the long-term effects of anthropogenic disturbances on understorey vegetation remain unclear, particularly compared with those in primary forests.

show abstract

High‐severity fire drives persistent floristic homogenization in human‐altered forests

et al. 2023

View full text Add to dashboard Cite

Ecological disturbance regimes across the globe are being altered via direct and indirect human influences. Biodiversity loss at multiple scales can be a direct outcome of these shifts. Fire, especially in dry forests, is an ecological disturbance that is experiencing dramatic changes due to climate change, fire suppression, increased human population in fire-prone areas, and alterations to vegetation composition and structure. Dry western conifer forests that historically experienced frequent, low-severity fires are now increasingly burning at high severity. Relatively little work has been done looking at the effects of this novel disturbance type on affected plant communities, and little is known about how these impacts change over time. To fill in these knowledge gaps, we examined a fire that burned in a yellow pine and mixed conifer forest in the central Sierra Nevada in California, USA. We sampled at five time steps across the nine years following the fire (1, 3, 5, 8, and 9 years postfire). We found a generally unimodal relationship between fire severity and plant alpha and gamma diversity, but found that areas that burned at high severity supported progressively lower plant diversity as time since fire increased. Similarly, beta diversity decreased drastically through time for the high-severity areas, while remaining more static in the other severity classes. The combination of these findings indicates that significant floristic homogenization can result from high-severity fire in this ecosystem type. We also saw consistently lower diversity in unburned areas in comparison to area burned at low and moderate severity, underlining that both lack of fire and high-severity fire can have negative impacts on postfire plant diversity. Unburned areas that experienced forest thinning after the first sample year saw an increase in plant diversity over time, suggesting that some-but not all-of the effects of fire on plant diversity can be approximated through forest management.

show abstract

Effects of thinning and prescribed fire frequency on ground flora in mixed Pinus-hardwood stands

Cited by 29 publications

References 69 publications

Understory Vegetation Responses to 15 Years of Repeated Fuel Reduction Treatments in the Southern Appalachian Mountains, USA

Understory Vegetation Responses to 15 Years of Repeated Fuel Reduction Treatments in the Southern Appalachian Mountains, USA

Forest Understorey Vegetation: Colonization and the Availability and Heterogeneity of Resources

High‐severity fire drives persistent floristic homogenization in human‐altered forests

Contact Info

Product

Resources

About