DOI: 10.5061/dryad.1c59zw42m
title: Data from: Modelling height–diameter relationships in living Araucaria (Araucariaceae) trees to reconstruct ancient araucarian conifer height

description: To reconstruct a fossil forest in three dimensions, an accurate estimation
 of tree height is crucial. However, modelling the height–diameter
 relationship of ancient trees is difficult, because the trunks of fossil
 trees are usually fragmentary, which makes direct height measurements
 impossible. One practical approach for reconstructing ancient tree height
 is to use growth models based on the height–diameter relationships of the
 nearest living relatives of the fossil taxa. Here we apply 19 growth
 models to describe height–diameter relationships of living Araucaria trees
 for establishing good growth models for ancient Araucariaceae trees. Data
 come from four living populations of the genus Araucaria: Araucaria
 bidwillii and A. cunninghamii in Queensland, Australia, and A.
 cunninghamii and A. hunsteinii in New Guinea. According to an AIC-based
 model selection, a Power model with an exponent of 0.67 (termed here the
 modified Mosbrugger model) is the best for each population and for the
 entire dataset (157 trees), but normalization constants differ across
 populations. To find the best models for the genus Araucaria, 100 random
 samples (each population generating 25 random samples) from the entire
 dataset are tested. Based on 100 curve fitting results on each model and
 multiple performance criteria, three median models are generated from the
 medians of their parameter estimates. The median Power model works best
 for Araucaria, but the modified Mosbrugger and Curtis models perform
 similarly well. In a case study, we revise tree heights of Upper Jurassic
 araucariaceous logs in Utah, USA, by applying these three models.
description: We compiled datasets on tree height–diameter information from
 three <em>Araucaria</em> species: <em>Araucaria
 bidwillii</em>, <em>A</em>.<em>
 cunninghamii</em> and <em>A</em>.
 <em>hunsteinii</em>. These datasets had originally been
 collected to determine the size composition of natural stands, describe
 forest structure, or analyse height–diameter relationships. However,
 standard in each of these studies was taking the diameter at breast height
 (DBH) of each tree trunk and the height (<em>H</em>) of the
 respective tree. In our study, we used both measurements to establish the
 height–diameter growth models presented here.
description: # Data from: Modelling height–diameter relationships in living *Araucaria*
 (Araucariaceae) trees to reconstruct ancient araucarian conifer height
 We compiled datasets on
 tree height–diameter information from three *Araucaria* species:
 *Araucaria bidwillii*, *A. cunninghamii* and *A. hunsteinii*. In total, we
 collected and analysed the height–diameter data of 157 *Araucaria* trees.
 These trees grew in different forests of New Guinea and eastern Australia
 (Queensland). The goal of this study is to describe height–diameter
 relationships of living *Araucaria* trees for establishing appropriate
 growth models for ancient araucarian trees. 19 models were fitted and
 ranked (see details in the related publication, DOI: 10.1111/pala.12693). 
 ## Description of the data and file structure Two variables are included
 in each dataset, i.e., DBH (diameter at breast height, m) and height (m).
 * 157 trees of *Araucaria*, totally (files: Araucaria_NG_and_QLD_sorted,
 and Auracaria_four_populations) * 54 trees of *A. bidwillii*
 in Queensland (file: Araucaria_bidwillii_in_Queensland_sorted) * 47 trees
 of *A. cunninghamii* in Queensland (file:
 Araucaria_cunninghamii_in_Queensland_sorted) * 31 trees of *A.
 cunninghamii* in New Guinea (file:
 Araucaria_cunninghamii_in_New_Guinea_sorted) * 25 trees of *A. hunsteinii*
 in New Guinea (file: Araucaria_hunsteinii_in_New_Guinea_sorted) * 100
 random samples; each random sample consisted of all 25 trees of *A.
 hunsteinii* from New Guinea, 25 randomly selected trees of *A.
 cunninghamii* from New Guinea, 25 randomly selected trees of *A.
 bidwillii* from Queensland, and 25 randomly selected trees of *A.
 cunninghamii* from Queensland (file: Sample_1 to Sample_100) ##
 Sharing/Access information N/A ## Code/Software All *Araucaria*
 height–diameter information was extracted with WebPlotDigitizer 4.2
 (WebPlotDigitizer, Pacifica, California, USA; Rohatgi 2020) from graphs in
 published papers (Paijmans 1970; Gray 1975; Pole 1999). All statistical
 analysis were performed with the free software R statistics (version
 4.1.1, ) using only built-in functions.
 Nonlinear curve fitting was done with the R function *nls*.