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Seedling and tree data from Sequoia National Park and Yosemite National Park

August 2, 2019

These tables include data from 25 long-term forest plots located in either Sequoia or Yosemite national park. Trees in these plots (established between 1982 and 2001) are censused annually for mortality and measured for diameter every 4 to 6 years. Plots were mostly 1 hectare (ha) in size (range 0.9 - 2.5 ha) and contained at least two 25 by 25 meter seedling sub-plots to monitor natural seedling recruitment. The largest plot, at 2.5 ha, included four such seedling sub-plots. Each sub-plot was divided into 5 by 5 meter quadrats. In almost all the plots these seedling sub-plots were established in 1999, but four plots (those with names starting with FF) were added to the study in 2002 and seedling data was only available from this date. Seedlings taller than 10 centimeters (which were at least 3 years old) were given numbered tags so that their survival and height class could be recorded individually. If there were more than 20 seedlings per quadrat of a species entering the greater-than-10 centimeters category, a sample of 20 was tagged, but this was unusual. Individual-level mortality and growth could be tracked for these seedlings. In each annual seedling census, the presence of the tagged seedling (live or dead) was recorded and it was assigned to a height category (10-25 cm, 25-50 cm, 50-75 cm, 75-100 cm, and 100-137 cm). Those that grew to 137 centimeters (tall enough to record a diameter-at-breast height (DBH)) were re-tagged as trees.

This release contains 2 CSV and 3 TXT files: TaggedSdl.txt, PlotInfogeneral.txt, quadrat_precise.csv, treedata.csv, and treeyears.txt.
These data support the following publication:
Moran, E., Das, AJ, Keeley, JE, & Stephenson, NL. (2019). Negative impacts of summer heat on Sierra Nevada tree seedlings. UC Merced.