Subalpine seedling establishment and climate data provide broad scale drivers of subalpine tree establishment patterns

The data presented from this study capture subalpine tree seedling characteristics and climatic drivers of establishment of 229 Engelmann spruce and subalpine fir tree seedlings sampled between 1996 and 2017 in beetle-affected and postfire subalpine stands of Colorado and Wyoming. These data include seedling ages ascertained from dendrochronological techniques that include counting annual growth rings. Additionally, age proxies from height and terminal bud scar count techniques are included, allowing the comparison of seedling ages derived from growth rings to age estimates derived from proxies. Maximum growth ring counts were used to calculate establishment dates for each seedling sample. Also included is a data file containing climatic variables from TerraClimate including growing season (May-September) average maximum temperature, minimum temperature, precipitation, and soil moisture in addition to annual average vapor pressure and climatic water deficits for each year from 1958-2017.
The seedling data were collected to elucidate establishment dates of Engelmann spruce and subalpine fir tree seedlings from disturbed stands. Seedlings were collected from bark beetle affected stands, which maintain partially closed canopies and allow for suppressed seedling growth, as well as high-severity burned areas, which have little to no canopy cover and an abundance of light resources. Climatic variables during years of seedling establishment were used in analyses to elucidate broadscale drivers of tree seedling recruitment in disturbed subalpine stands.
The metadata for this data publication was originally published on 02/02/2021, with data under embargo. Minor metadata updates were made on 05/18/2021. On 06/30/2021 the data embargo was lifted and data became available. Additional minor metadata updates were made on 10/30/2024.