Precommercial thinning direct-seeded longleaf pine data on a poor site

A poor longleaf site in Rapides Parish, Louisiana was direct-seeded in 1965 and then thinned in 1974 using several different levels of thinning that ranged from thinning to 3000 trees per acre to thinning to 500 trees per acre as well as a treatment that included cutting all trees in strips. The data included in this publication contain tree measurements collected after thinning and repeated every 5 or more years until the study was closed, which resulted in the following data collection years: 1979, 1984, 1989, 2002, and 2009. Measurements include approximate age of stand and diameter at breast height for every tree in each plot. Also included for a subset of trees each year is: height to base of live crown, tree height, crown class, bark thickness in two directions, and height of trees to 4 different outside bark diameters (2, 4, 6, and 8 inches).
The original study was meant to be used in conjunction with other studies on other sites for determining the best thinning method for dense direct-seeded longleaf pine stands.
These data were originally published on 05/20/2021. On 11/09/2021 a reference was added for a newly published and related data publication (https://doi.org/10.2737/RDS-2021-0097).

美国路易斯安那州拉皮兹堂区一处贫瘠长叶松立地，于1965年实施直接播种造林，1974年开展多梯度间伐处理，间伐强度覆盖每英亩保留3000株至500株的区间，同时设置带状全伐林木的对照处理。
本出版物收录的数据集包含间伐后采集的林木测量数据，后续每5年及以上重复测量一次，直至研究终止，最终数据采集年份为1979、1984、1989、2002与2009年。测量指标涵盖每块样地内所有林木的林分近似年龄与胸径。此外，每年还会针对部分林木采集以下数据：活冠基部高度、树高、冠级、双向树皮厚度，以及对应4种不同去皮前直径（2、4、6、8英寸）的树木高度。
本原始研究旨在与其他立地的同类研究结合，用于确定致密直接播种长叶松林分的最优间伐方法。
该数据集最初于2021年5月20日发布，2021年11月9日补充了一篇相关的新近发表数据出版物的参考文献（https://doi.org/10.2737/RDS-2021-0097）。