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All plant species were identified down to finest taxa when possible. Each plant code used in the survey data is paired to a plant code on this species list which provides the full scientific name of each species, the plant family the species belongs to, the native or non-native status of species, and the life history of the plant. Plant nomenclature follows: Baldwin B.G., D.H. Goldman, D.J. Keil, R. Patterson, T.J. Rosatti, and D.H. Wilken, editors. 2012. The Jepson Manual: vascular plants of California. Second edition. University of California Press, Berkeley, USA.
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Physical site characteristics including aspect, elevation, and slope were recorded for each study plot and spatial coordinates were obtained from a global positioning system. Stand height was determined by averaging the heights of the first live woody individual encountered along each 10 m subplot in mechanically masticated plots as well as in the adjacent controls. Unfortunately height data was not collected from postfire plots in the prior study. The age of the stand prior to each mechanical disturbance was obtained from stem samples collected from the first two obligate seeding individuals encountered within controls and ranged from seven to sixty-four years across all mechanically masticated fuel treatments....
Abstract (from Ecological Society of America): Large, severe fires are becoming more frequent in many forest types across the western United States and have resulted in tree mortality across tens of thousands of hectares. Conifer regeneration in these areas is limited because seeds must travel long distances to reach the interior of large burned patches and establishment is jeopardized by increasingly hot and dry conditions. To better inform postfire management in low elevation forests of California, USA, we collected 5‐year postfire recovery data from 1,234 study plots in 19 wildfires that burned from 2004–2012 and 18 years of seed production data from 216 seed fall traps (1999–2017). We used this data in conjunction...
Categories: Publication; Types: Citation
Ecosystems are dynamic systems with complex responses to environmental variation. In response to pervasive stressors of changing climate and disturbance regimes, many ecosystems are realigning rapidly across spatial scales, in many cases moving outside of their observed historical range of variation into alternative ecological states. In some cases, these new states are transitory and represent successional stages that may ultimately revert to the pre-disturbance condition; in other cases, alternative states are persistent and potentially self-reinforcing, especially under conditions of altered climate, disturbance regimes, and influences of non-native species. These reorganized states may appear novel, but reorganization...
Categories: Publication; Types: Citation
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The sampling design at each of the 149 mechanically masticated fuel treatment study sites consisted of a 10 x 100 m plot established within the treated area at the random point generated in ArcGIS and an adjacent 10 x 100 m control plot placed one meter inside the edge of untreated vegetation to avoid edge affects. Each study plot was further subdivided into 10 100-m2 subplots with a nested 1-m2 quadrat placed along the top edge of the measurement tape. Postfire study sites consisted of a 20 x 50 m plot that was equal in area to a fuel treatment study plot and was also further subdivided into 10 100-m2 subplots with a nested 1-m2 quadrat placed along the outer top and bottom edges of the plot. Cover and density...
Large, severe fires are becoming more frequent in many forest types across the western United States and have resulted in tree mortality across tens of thousands of hectares. Conifer regeneration in these areas is limited because seeds must travel long distances to reach the interior of large burned patches and establishment is jeopardized by increasingly hot and dry conditions. To better inform postfire management in low elevation forests of California, USA, we collected 5‐yr postfire recovery data from 1,234 study plots in 19 wildfires that burned from 2004–2012 and 18 yrs of seed production data from 216 seed fall traps (1999–2017). We used these data in conjunction with spatially extensive climate, topography,...
Categories: Publication; Types: Citation
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Abstract Ecological factors favoring either resprouting or obligate seeding in plants have received considerable attention recently. Three ecological models have been proposed to explain patterns of these two life history types. In this study we test these three models using data from California chaparral. We take an innovative approach to testing these models by not testing community or landscape patterns, but instead, investigating environmental patterns characteristic of pairs of either resprouting or obligate seeding subspecies of Arctostaphylos (Ericaceae), a dominant and diverse shrub genus in chaparral. Four species were investigated that contain both a resprouting and an obligate seeding subspecies. Data...
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Abstract Background Forest and nonforest ecosystems of the western United States are experiencing major transformations in response to land-use change, climate warming, and their interactive effects with wildland fire. Some ecosystems are transitioning to persistent alternative types, hereafter called “vegetation type conversion” (VTC). VTC is one of the most pressing management issues in the southwestern US, yet current strategies to intervene and address change often use trial-and-error approaches devised after the fact. To better understand how to manage VTC, we gathered managers, scientists, and practitioners from across the southwestern US to collect their experiences with VTC challenges, management responses,...
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Mechanical fuel treatments are a primary pre-fire strategy for potentially mitigating the threat of wildland fire, yet there is limited information on how they impact shrubland ecosystems. This publication contains data related to vegetation structure and composition in mechanically masticated chaparral communities used to assess the impact of these fuel treatments on shrubland vegetation and to determine the extent to which they emulate postfire succession. Data were collected from within chaparral dominated communities on the Angeles, Cleveland, Los Padres, and San Bernardino national forests of southern California. The climate of the region is Mediterranean with mild, wet winters and hot, dry summers and the...
Reproduction is a key component of ecological resilience in forest ecosystems, so understanding how seed production is influenced by extreme drought is key to understanding forest recovery trajectories. If trees respond to mortality-inducing drought by preferentially allocating resources for reproduction, the recovery of the stand to pre-drought conditions may be enhanced accordingly. We used a 20-year annual seed capture data set to investigate whether seed production by three tree genera commonly found in the Sierra Nevada (Abies, Pinus, and Calocedrus) was correlated with variation in local weather, which included an extreme drought spanning multiple years. We tested whether average seed production differed during...
Categories: Publication; Types: Citation


    map background search result map search result map Arctostaphylos Occurrence and Historical Fires Table Survey Data for Chaparral Vegetation in Masticated Fuel Treatments on the Four Southern California National Forests (2011-2012) Site Data Species List Survey Data Vegetation type conversion in the US Southwest: frontline observations and management responses Survey Data for Chaparral Vegetation in Masticated Fuel Treatments on the Four Southern California National Forests (2011-2012) Site Data Species List Survey Data Arctostaphylos Occurrence and Historical Fires Table Vegetation type conversion in the US Southwest: frontline observations and management responses