Provided are data containing condition assessments on individual giant sequoia (Sequoiadendron giganteum; SEGI) stems and post-fire regeneration counts within Board Camp, Suwanee, New Oriole Lake, Homer’s Nose, and a subset of Redwood Mountain and Dillonwood groves of Sequoia and Kings Canyon national parks, respectively. Stem data contain condition-related attributes (e.g., spatial location, diameter breast height, status - live or dead, percent canopy that is live, scorched or torched). Regeneration plots are located using a spatially-balanced sampling design (Generalized Random Tessellation Stratified - 'GRTS'). Each regeneration plot is a fixed radius circle (11.35 meters or 17.84 meters) and contain count data of giant sequoia seedlings.

These datasets provide spatially-explicit estimates of the magnitude of giant sequoia foliage dieback along selected trail corridors in Sequoia and Kings Canyon national parks, California, from 2014 through 2017. They additionally provide giant sequoia tree-ring measurements, through the year 1989, for two locations in the Giant Forest grove, Sequoia National Park, California. These data support the following publications: Nathan L. Stephenson, Adrian J. Das, Nicholas J. Ampersee, Kathleen G. Cahill, Anthony C. Caprio, John E. Sanders, A. Park Williams, Patterns and correlates of giant sequoia foliage dieback during California’s 2012–2016 hotter drought, Forest Ecology and Management, Available online 7 November 2017, ISSN 0378-1127, https://doi.org/10.1016/j.foreco.2017.10.053. Martin, R. E., G. P. Asner, E. Francis, A. Ambrose, W. Baxter, A. J. Das, N. R. Vaughn, T. Paz-Kagan, T. Dawson, K. Nydick, and N. L. Stephenson. Submitted. Remote measurement of canopy water content in giant sequoias (Sequoiadendron giganteum) during drought. Submitted to special section in Forest Ecology and Management.

These data describe tree mortality and the factors associated with tree mortality for a variety of plots in Sequoia National Park. Most of the data were collected between 2014 and 2017 (during an extremely severe drought), along with some comparison data from 2004 to 2007.

This dataset records mortality-- including involvement of bark beetles-- and burn severity information for trees in long term forest dynamics plots in Sequoia National Park and Yosemite National Park that experienced fire.

These data include giant sequioa (Sequoiadendron giganteum) age and tree-ring data from measurements on 458 stumps. The original data were recorded on paper data sheets by Ellsworth Huntington and his assistants in 1911 and 1912; their methods are elaborated in Huntington (1914), and further details can be found in Stephenson and Demetry (1995). We entered the data from photocopies of the original data sheets which, to the best of our knowledge, reside at Yale University. The photocopies apparently were made in the late 1960s or early 1970s and were housed in Sequoia National Park’s archives. Most of Huntington’s 458 measured giant sequoia stumps were in or near what is now the Hume Lake District of Sequoia National Forest (Giant Sequoia National Monument), California, particularly the Converse Basin Grove; however, about 17 percent came from in or near what is now Mountain Home Demonstration State Forest, about 70 km to the SSE. Data for each tree (stump) consist of from one to five readings of the widths (to the nearest 0.5 mm) of groups of 10 tree rings along unique radii. When only one or two radii were measured on a stump, we entered the data for each radius. When three, four, or five radii were measured, we entered data from two radii whose directions differed by at least 90 degrees, whenever possible. The choice of entering data from widely separated radii was made by Stephenson and Demetry (1995), who wished to determine the effects of two widely separated increment cores on the accuracy and precision of age estimates for giant sequoias. Sometimes, “DO NOT USE” was written by Huntington across a radius’ readings, usually because that radius came out several to many decades younger than the oldest radius for that tree. If such a radius normally would fit our criterion to be entered in the database (because it was separated by at least 90 from the other radius we entered), a judgement was made. Generally, if the difference was at least 50 years, a different radius whose count better agreed with the largest count was chosen, regardless of its direction. References: Douglass, A. E. 1919. Climatic Cycles and Tree Growth, A Study of the Annual Rings of Trees in Relation to Climate and Solar Activity. Carnegie Institute of Washington. 127 pages. Huntington, E. 1914. The Climatic Factor as Illustrated in Arid America. Carnegie Institute of Washington Publication No. 192. 341 pages. Stephenson, N. L., and A. Demetry. 1995. Estimating ages of giant sequoias. Canadian Journal of Forest Research 25:223-233.

These data represent tree diameter, species, mortality status, and plot attributes from 164 plots in Sequoia and Kings Canyon national parks, California. Plots were matched with local records of recent fire history to determine burn status and year burned if applicable.

These data represent tree diameter, species, mortality status, and plot attributes from 164 plots in Sequoia and Kings Canyon national parks, California. Plots were matched with local records of recent fire history to determine burn status and year burned if applicable.

This dataset was used as part of a continent-wide analysis of tree fecundity and its association with climate and tree size. This dataset consists of: plotinfo.csv, which contains basic attribute information for the field plots where the data were collected; seeddata.csv, which contains the data for seeds collected (how many, what type, etc.); trapxycoord.csv, which contains location and identification information for the seed traps used to collect the seeds; treexycoord.csv, which contains location and attribute information for the standing trees in the plot where the seeds were collected; and treedata.csv, which contains data on the size and species of standing trees in the plot where the seeds were collected.

We established a network of 121 plots distributed within the 2020 SQF, 2020 Rattlesnake, and 2021 KNP complex fire footprints (extracted from Fire and Resource Assessment Program (FRAP), https://frap.fire.ca.gov), as well as outside the fire perimeters to provide an unburned comparison. These plots were combined from two projects: a fire and fuels study (F&F) and the USGS sequoia research program (SRP), a related study of sequoia grove condition. All plots were visited in the summer of 2022, and thus we captured dynamics 1 and 2 years post-fire. Plots were restricted to conifer forest types, informed by a Sequoia and Kings Canyon national parks (SEKI) vegetation classification geospatial layer. F&F plots (102 in total) were stratified by elevation bands (1500-1917, 1917-2333, 2333-2750 m) and satellite-derived metrics of fire severity. SRP plots (19 in total) were placed in both burned and unburned giant sequoia groves. In all, 45 plots were located across eleven giant sequoia groves, with the remaining 76 plots located outside of groves.

These data were collected to quantify oak mortality during the 2014-2017 drought. 30 tenth hectare drought plots were established throughout the blue oak woodland of Sequoia National Park. Information on species, size, and mortality were collected for all standing trees in each plot. In addition, two long-term 2.25 ha plots were established, in which the same data were collected.