Quaking aspen persistence in three Oregon landscapes

Quaking aspen (Populus tremuloides) is an important tree species in the western United States and there has been much concern about its persistence. In this thesis, I report on aspen in a portion of its range that has not been previously evaluated: the eastern and western slopes of the Central Oregon Cascades and the Willamette Valley. My primary research objectives for each of the three landscapes were to: (1) assess aspen overstory recruitment across time; (2) assess the condition of aspen sprouts; (3) identify environmental and biological stressors to the aspen overstory and understory; and (4) test the aspen overstory, recent recruitment, and sprouts for correlations to ungulate herbivory and conifer encroachment. In addition, on the eastern slope of the Cascades, I tested the efficacy of piles of coarse woody debris (CWD) or jackstraw as an herbivore deterrent. On the east side of the Cascade Mountains, aspen stands were small (≤ 0.6 ha) and found in a dense conifer matrix. Small stands are expected to recruit overstory across time and expand with disturbance events. Aspen stands on the east side showed a steady decline in overstory recruitment that coincided with increase in conifer encroachment and ungulate herbivory. Aspen stands with conifer mortality attributable to mountain pine beetle (Dendroctonus ponderosae), and subsequent release of overstory competition and formation of jackstraw, recruited overstory trees at expected levels. More than 75% of all recently recruited trees (< 20 years) were behind jackstraw. Diseased sprouts protected from herbivores recruited into the overstory. My results suggest that aspen sprouts increase in height when released from herbivory and increase in density when released from conifer shading and competition. Accordingly, I suggest that the mountain pine beetle has a powerful ecological effect that can help aspen recruit at the stand level and persist at the landscape level via: (1) removal of conifer shading and resource competition; (2) creation of snags, and subsequent increase in jackstraw; and (3) the ensuing increase in sprout density and heights, which leads to overstory recruitment. Results in the two western Oregon landscapes show aspen stands are small (< 0.1 ha), rare, and in decline. Stand origins are unknown and could be genetically linked to stands on the east Cascades or to the north. While most aspen stems dated back to the early to mid 1900s, one stem originated in the mid 1800s. I classified 16 aspen stands from these two landscapes into 6 stand types: Snowfield, Upland Aspen/Conifer, Meadow Fringe, Lithic/Boulder, Pasture Valley, and Riparian Valley. One stand type was found increasing, 3 types were decreasing, and 2 types were at risk of loss. I found aspen sprouts were suppressed by herbivory, disease, and conifer encroachment. Some stand types showed aspen overstory at risk from conifer encroachment. Aspen is on the fringe of its range on the east and west slopes of the Oregon Cascades and in the Willamette Valley. A scientific understanding of aspen in these three landscapes may help the persistence of this species in the face of climate change

Aspen Restoration and Social Agreements : An Introductory Guide for Forest Collaboratives in Central and Eastern Oregon

Collaborative Regional Learning This document is part of a forest collaborative regional learning project on aspen restoration and social agreements. Thanks to all the individuals, collaborative groups, and organizations who provided feedback and suggestions. We appreciate the participation of members from: Blue Mountains Forest Partners, Deschutes Collaborative Forest Project, Harney County Restoration Collaborative, Ochoco Forest Restoration Collaborative, Umatilla Forest Collaborative Group, and Wallow-Whitman Forest Collaborative.Quaking aspen (Populus tremuloides) is one of the few hardwood trees found outside of riparian areas across central and eastern Oregon. Although aspen makes up less than 1% of total acres in Oregon’s eastside forests, it supports a disproportionate amount of wildlife, plants, and insects compared to surrounding coniferous forests. Aspen stands and ecosystems are one of the most biodiverse habitat types in the conifer forest systems of central and eastern Oregon; second only to riparian areas for species richness and diversity. Yet the total acres of aspen ecosystems and habitat have decreased greatly (possibly by as much as 80%) and are at risk of disappearing across some regions (see Section 4: Aspen in Central Oregon and the Blue Mountains). Many forest collaborative groups in the region have voiced an interest in addressing aspen restoration on their public lands of focus or Collaborative Forest Landscape Restoration (CLFR) projects. These groups consist of diverse stakeholders who work together to support forest restoration on public lands for mutual ecological, economic, and social outcomes through consensus-based dialogue and decision making. This often occurs during the management agency’s planning or NEPA process. Although the agency retains final decision-making authority, common ground agreements that collaboratives achieve can assist in identifying socially acceptable restoration treatments, and are intended, in part, to reduce the likelihood of objections and litigation. This document highlights the social and ecological importance of aspen, provides some basic information on aspen restoration, and points the reader to in-depth science synthesis papers to assist with restoration guidelines and developing collaborative input. It may help collaboratives start a conversation and move toward social agreement on why, how, and where to prioritize aspen restoration; and the tools and approaches provided may also be useful for other issues

TOI-4010: A System of Three Large Short-Period Planets With a Massive Long-Period Companion

We report the confirmation of three exoplanets transiting TOI-4010 (TIC-352682207), a metal-rich K dwarf observed by TESS in Sectors 24, 25, 52, and 58. We confirm these planets with HARPS-N radial velocity observations and measure their masses with 8 - 12% precision. TOI-4010 b is a sub-Neptune ($P = 1.3$ days, $R_{p} = 3.02_{-0.08}^{+0.08}~R_{\oplus}$, $M_{p} = 11.00_{-1.27}^{+1.29}~M_{\oplus}$) in the hot Neptune desert, and is one of the few such planets with known companions. Meanwhile, TOI-4010 c ($P = 5.4$ days, $R_{p} = 5.93_{-0.12}^{+0.11}~R_{\oplus}$, $M_{p} = 20.31_{-2.11}^{+2.13}~M_{\oplus}$) and TOI-4010 d ($P = 14.7$ days, $R_{p} = 6.18_{-0.14}^{+0.15}~R_{\oplus}$, $M_{p} = 38.15_{-3.22}^{+3.27}~M_{\oplus}$) are similarly-sized sub-Saturns on short-period orbits. Radial velocity observations also reveal a super-Jupiter-mass companion called TOI-4010 e in a long-period, eccentric orbit ($P \sim 762$ days and $e \sim 0.26$ based on available observations). TOI-4010 is one of the few systems with multiple short-period sub-Saturns to be discovered so far.Comment: 26 pages, 16 figures, published in A

A Super-Earth and Sub-Neptune Transiting the Late-type M Dwarf LP 791-18

Planets occur most frequently around cool dwarfs, but only a handful of specific examples are known to orbit the latest-type M stars. Using TESS photometry, we report the discovery of two planets transiting the low-mass star called LP 791-18 (identified by TESS as TOI 736). This star has spectral type M6V, effective temperature 2960 K, and radius 0.17 R o, making it the third-coolest star known to host planets. The two planets straddle the radius gap seen for smaller exoplanets; they include a 1.1R ⊕ planet on a 0.95 day orbit and a 2.3R ⊕ planet on a 5 day orbit. Because the host star is small the decrease in light during these planets' transits is fairly large (0.4% and 1.7%). This has allowed us to detect both planets' transits from ground-based photometry, refining their radii and orbital ephemerides. In the future, radial velocity observations and transmission spectroscopy can both probe these planets' bulk interior and atmospheric compositions, and additional photometric monitoring would be sensitive to even smaller transiting planets

TNC_ASPEN_SEC 3.pdf

Collaborative Regional Learning This document is part of a forest collaborative regional learning project on aspen restoration and social agreements. Thanks to all the individuals, collaborative groups, and organizations who provided feedback and suggestions. We appreciate the participation of members from: Blue Mountains Forest Partners, Deschutes Collaborative Forest Project, Harney County Restoration Collaborative, Ochoco Forest Restoration Collaborative, Umatilla Forest Collaborative Group, and Wallow-Whitman Forest Collaborative.Quaking aspen (Populus tremuloides) is one of the few hardwood trees found outside of riparian areas across central and eastern Oregon. Although aspen makes up less than 1% of total acres in Oregon’s eastside forests, it supports a disproportionate amount of wildlife, plants, and insects compared to surrounding coniferous forests. Aspen stands and ecosystems are one of the most biodiverse habitat types in the conifer forest systems of central and eastern Oregon; second only to riparian areas for species richness and diversity. Yet the total acres of aspen ecosystems and habitat have decreased greatly (possibly by as much as 80%) and are at risk of disappearing across some regions (see Section 4: Aspen in Central Oregon and the Blue Mountains). Many forest collaborative groups in the region have voiced an interest in addressing aspen restoration on their public lands of focus or Collaborative Forest Landscape Restoration (CLFR) projects. These groups consist of diverse stakeholders who work together to support forest restoration on public lands for mutual ecological, economic, and social outcomes through consensus-based dialogue and decision making. This often occurs during the management agency’s planning or NEPA process. Although the agency retains final decision-making authority, common ground agreements that collaboratives achieve can assist in identifying socially acceptable restoration treatments, and are intended, in part, to reduce the likelihood of objections and litigation. This document highlights the social and ecological importance of aspen, provides some basic information on aspen restoration, and points the reader to in-depth science synthesis papers to assist with restoration guidelines and developing collaborative input. It may help collaboratives start a conversation and move toward social agreement on why, how, and where to prioritize aspen restoration; and the tools and approaches provided may also be useful for other issues

TNC_ASPEN_SEC 4.pdf

Collaborative Regional Learning This document is part of a forest collaborative regional learning project on aspen restoration and social agreements. Thanks to all the individuals, collaborative groups, and organizations who provided feedback and suggestions. We appreciate the participation of members from: Blue Mountains Forest Partners, Deschutes Collaborative Forest Project, Harney County Restoration Collaborative, Ochoco Forest Restoration Collaborative, Umatilla Forest Collaborative Group, and Wallow-Whitman Forest Collaborative.Quaking aspen (Populus tremuloides) is one of the few hardwood trees found outside of riparian areas across central and eastern Oregon. Although aspen makes up less than 1% of total acres in Oregon’s eastside forests, it supports a disproportionate amount of wildlife, plants, and insects compared to surrounding coniferous forests. Aspen stands and ecosystems are one of the most biodiverse habitat types in the conifer forest systems of central and eastern Oregon; second only to riparian areas for species richness and diversity. Yet the total acres of aspen ecosystems and habitat have decreased greatly (possibly by as much as 80%) and are at risk of disappearing across some regions (see Section 4: Aspen in Central Oregon and the Blue Mountains). Many forest collaborative groups in the region have voiced an interest in addressing aspen restoration on their public lands of focus or Collaborative Forest Landscape Restoration (CLFR) projects. These groups consist of diverse stakeholders who work together to support forest restoration on public lands for mutual ecological, economic, and social outcomes through consensus-based dialogue and decision making. This often occurs during the management agency’s planning or NEPA process. Although the agency retains final decision-making authority, common ground agreements that collaboratives achieve can assist in identifying socially acceptable restoration treatments, and are intended, in part, to reduce the likelihood of objections and litigation. This document highlights the social and ecological importance of aspen, provides some basic information on aspen restoration, and points the reader to in-depth science synthesis papers to assist with restoration guidelines and developing collaborative input. It may help collaboratives start a conversation and move toward social agreement on why, how, and where to prioritize aspen restoration; and the tools and approaches provided may also be useful for other issues

TNC_ASPEN_SEC 5.pdf

Collaborative Regional Learning This document is part of a forest collaborative regional learning project on aspen restoration and social agreements. Thanks to all the individuals, collaborative groups, and organizations who provided feedback and suggestions. We appreciate the participation of members from: Blue Mountains Forest Partners, Deschutes Collaborative Forest Project, Harney County Restoration Collaborative, Ochoco Forest Restoration Collaborative, Umatilla Forest Collaborative Group, and Wallow-Whitman Forest Collaborative.Quaking aspen (Populus tremuloides) is one of the few hardwood trees found outside of riparian areas across central and eastern Oregon. Although aspen makes up less than 1% of total acres in Oregon’s eastside forests, it supports a disproportionate amount of wildlife, plants, and insects compared to surrounding coniferous forests. Aspen stands and ecosystems are one of the most biodiverse habitat types in the conifer forest systems of central and eastern Oregon; second only to riparian areas for species richness and diversity. Yet the total acres of aspen ecosystems and habitat have decreased greatly (possibly by as much as 80%) and are at risk of disappearing across some regions (see Section 4: Aspen in Central Oregon and the Blue Mountains). Many forest collaborative groups in the region have voiced an interest in addressing aspen restoration on their public lands of focus or Collaborative Forest Landscape Restoration (CLFR) projects. These groups consist of diverse stakeholders who work together to support forest restoration on public lands for mutual ecological, economic, and social outcomes through consensus-based dialogue and decision making. This often occurs during the management agency’s planning or NEPA process. Although the agency retains final decision-making authority, common ground agreements that collaboratives achieve can assist in identifying socially acceptable restoration treatments, and are intended, in part, to reduce the likelihood of objections and litigation. This document highlights the social and ecological importance of aspen, provides some basic information on aspen restoration, and points the reader to in-depth science synthesis papers to assist with restoration guidelines and developing collaborative input. It may help collaboratives start a conversation and move toward social agreement on why, how, and where to prioritize aspen restoration; and the tools and approaches provided may also be useful for other issues

TNC_ASPEN_FULL DOC_FINAL for web.pdf

Collaborative Regional Learning This document is part of a forest collaborative regional learning project on aspen restoration and social agreements. Thanks to all the individuals, collaborative groups, and organizations who provided feedback and suggestions. We appreciate the participation of members from: Blue Mountains Forest Partners, Deschutes Collaborative Forest Project, Harney County Restoration Collaborative, Ochoco Forest Restoration Collaborative, Umatilla Forest Collaborative Group, and Wallow-Whitman Forest Collaborative.Quaking aspen (Populus tremuloides) is one of the few hardwood trees found outside of riparian areas across central and eastern Oregon. Although aspen makes up less than 1% of total acres in Oregon’s eastside forests, it supports a disproportionate amount of wildlife, plants, and insects compared to surrounding coniferous forests. Aspen stands and ecosystems are one of the most biodiverse habitat types in the conifer forest systems of central and eastern Oregon; second only to riparian areas for species richness and diversity. Yet the total acres of aspen ecosystems and habitat have decreased greatly (possibly by as much as 80%) and are at risk of disappearing across some regions (see Section 4: Aspen in Central Oregon and the Blue Mountains). Many forest collaborative groups in the region have voiced an interest in addressing aspen restoration on their public lands of focus or Collaborative Forest Landscape Restoration (CLFR) projects. These groups consist of diverse stakeholders who work together to support forest restoration on public lands for mutual ecological, economic, and social outcomes through consensus-based dialogue and decision making. This often occurs during the management agency’s planning or NEPA process. Although the agency retains final decision-making authority, common ground agreements that collaboratives achieve can assist in identifying socially acceptable restoration treatments, and are intended, in part, to reduce the likelihood of objections and litigation. This document highlights the social and ecological importance of aspen, provides some basic information on aspen restoration, and points the reader to in-depth science synthesis papers to assist with restoration guidelines and developing collaborative input. It may help collaboratives start a conversation and move toward social agreement on why, how, and where to prioritize aspen restoration; and the tools and approaches provided may also be useful for other issues