DOI: 10.5061/dryad.fttdz0916
title: Data from: Assisted migration of cloud forest trees: Unearthing the effects of climatic transfer distance

description: We planted 30 seedlings of 13 shade-tolerant tropical montane cloud forest
 tree species in eight forest sites (3120 seedlings in total) along an
 elevation gradient (1250 to 2429 m a.s.l.) in central-eastern Mexico. We
 recorded sapling survival and relative growth rate in height (RGRh) and
 diameter (RGRd) after eight years. We tested the survival and growth
 response for all species together to the effect of Climatic Transfer
 Distance (CTD; the difference between the historical climate at the seed
 source and the current climate at translocation sites) in terms of mean
 annual temperature (CTD_MAT), maximum and minimum annual temperatures
 (CTD_Tmax and CTD_Tmin), mean annual precipitation (CTD_MAP), and climate
 moisture deficit (CTD_CMD). We also tested the sapling response to the
 climatic variables at the translocation site. We found evidence to support
 the decline, although slight, in tree sapling survival and growth across
 tree species with increasing CTD, thus supporting the hypothesis of a
 reduction in performance with increasing distance between the climate to
 which tree species are adapted (historic climate of seed origin) and that
 at the new translocation sites. Our results support a higher mortality
 risk caused by increasing CTD in MAP and MAT and a decline in growth
 caused by the increasing CTD in MAT, Tmax, MAP, and CMD. Although high
 variation occurred among species, this general pattern still emerged and
 was consistent for all the climatic variables.
description: A total of eight forest sites were selected to establish the
 plantings in field common gardens along an elevation gradient (1250 to
 2429 m a.s.l.) in Veracruz, Mexico. In each site, a 50 × 55 m plot was
 delimited, fenced, and 30 seedlings of each of 13 tropical montane cloud
 forest tree species were transplanted in May-June 2015. Species were
 distributed at random within each plot and the individuals were planted
 ~2.6 m apart. A ~1 m radius around each seedling was weeded at planting
 time, and again after three, six and 12 months. Survival, height, and
 diameter at the base of all plants were recorded immediately after
 planting and after 8 years. The relative growth rates in height and
 diameter (RGRh and RGRd, respectively) were calculated following Hunt
 (1982).  To test the climate sensitivity of the young
 tree stages, we selected the following five climate variables: mean annual
 temperature (MAT), mean annual precipitation (MAP), mean minimum
 temperature in the coldest month (Tmin), mean maximum temperature in the
 warmest month (Tmax), and Hargreave’s Climate Moisture Deficit (CMD). The
 climate data for each seed source (average 1961-1990) and translocation
 site (average 2015-2022) were downloaded from the ClimateNA data portal
 (https://climatena.ca/), based on Wang et al. (2016). For each
 georeferenced location of a tree species´ seed source (seed trees), we
 extracted the climatic variables for the reference period 1961 – 1990,
 assuming that this represents the climate to which the seed trees were
 adapted. We refer to this 1961 –1990 period as the “historic climate”. For
 the field translocation sites, climate data were obtained for the period
 in which the experimental transplants were actually grown (2015–2022), and
 this is referred to as the “contemporary climate”. To measure the impact
 of the difference between the historic and contemporary climates at each
 planting site, we estimated the Climatic Transfer Distance (CTD),
 <em>sensu</em> Leites et al. (2012) as: CTD = (contemporary
 climate at the test site) – (historic climate at the seed
 source). To evaluate the power of CTD as predictor of
 tree survival (binomial response variable), a Generalized Linear Mixed
 Model (GLMM; binomial family and logit link function) was used. CTD was
 included as a fixed-effects term and tree species as a random-effects
 term. In each full model, we also included the quadratic term for CTD
 considering that the optimum (highest survival) was expected to occur at
 the CTD with the value of zero (or closest to zero), and a decline would
 occur in either direction from the zero, describing a downward facing
 parabola. We included the climatic variables at the translocation site
 that were least correlated with the CTD variable (<em>R</em>
 &lt; 0.7) to fit the complete models. To fit the GLMM, we ran the
 function glmer with the package lme4 in R Statistical Environment (version
 4.2.2; (2022-10-31)(R Core Team, 2022). To evaluate the relative growth
 rate in height (RGRh) and diameter (RGRd) as a function of CTD, a Linear
 Mixed Model (LMM) with a normal error distribution was used. We also
 included the quadratic term for the CTD. The full models also included the
 climatic variable at the translocation site that was least correlated with
 the CTD variable. The function lmer of the package nlme was used to fit
 the LMM (Cayuela Delgado & De La Cruz, 2022).
 References Cayuela Delgado, L., & De
 La Cruz, R. O. T. (2022). <em>Análisis de datos ecológicos en
 R</em>. México: Ediciones Mundi-Prensa. Hunt, R.
 (1982). <em>Plant growth curves. The functional approach to plant
 growth analysis</em>. London, UK: Edward Arnold Ltd.
 Leites, L. P., Rehfeldt, G. E., Robinson, A. P., Crookston, N.
 L., & Jaquish, B. (2012). Possibilities and limitations of using
 historic provenance tests to infer forest species growth responses to
 climate change. <em>Natural Resource Modeling, 25</em>(3),
 409-433. doi:10.1111/j.1939-7445.2012.00129.x R Core
 Team, R. (2022). <em>R: A language and environment for statistical
 computing</em>. R Foundation for Statistical Computing. Vienna,
 Austria.URL https://www.R-project.org/.
 Wang, T. L., Hamann, A., Spittlehouse, D., & Carroll, C.
 (2016). Locally Downscaled and Spatially Customizable Climate Data for
 Historical and Future Periods for North America. <em>Plos One,
 11</em>(6), 17. doi:10.1371/journal.pone.0156720
description: # Data from: Assisted migration of cloud forest trees: Unearthing the
 effects of climatic transfer distance
 [https://doi.org/10.5061/dryad.fttdz0916](https://doi.org/10.5061/dryad.fttdz0916) We planted 30 seedlings of 13 shade-tolerant tropical montane cloud forest tree species in eight forest sites (3120 seedlings in total) along an elevation gradient (1250 to 2550 m a.s.l.) in central-eastern Mexico. We recorded sapling survival and relative growth rate in height (RGRh) and diameter (RGRd) after eight years. We tested the survival and growth response for all species together to the effect of Climatic Transfer Distance (CTD; the difference between the historical climate at the seed source and the current climate at translocation sites) in terms of mean annual temperature (CTD_MAT), maximum and minimum annual temperatures (CTD_Tmax and CTD_Tmin), mean annual precipitation (CTD_MAP), and climate moisture deficit (CTD-CMD). We also tested the sapling response to the climatic variables at the translocation site. ## Description of the data and file structure Plantings were established in 2015. Seedlings were one to two years old. Survival and growth in height and diameter were measured immediately after planting and 8 years after planting (in 2023). To test the climate sensitivity of the young tree stages, we selected the following five climate variables: mean annual temperature (MAT), mean annual precipitation (MAP), mean minimum temperature in the coldest month (Tmin), mean maximum temperature in the warmest month (Tmax), and Hargreave’s Climate Moisture Deficit (CMD). The climate data for each seed source (average 1961-1990) and translocation site (average 2015-2022) were downloaded from the ClimateNA data portal ([https://climatena.ca/](https://climatena.ca/)), based on Wang et al. (2016).  For each georeferenced location of a tree species´ seed source (seed trees), we extracted the climatic variables for the reference period 1961 – 1990, assuming that this represents the climate to which the seed trees were adapted. Hereafter, we refer to this 1961 –1990 period as the “historic climate”. For the field translocation sites, climate data were obtained for the period in which the experimental transplants were actually grown (2015–2022), and this is referred to hereafter as the “contemporary climate”. To measure the impact of the difference between the historic and contemporary climates at each planting site, we estimated the Climatic Transfer Distance (CTD), *sensu* Leites et al. (2012) as: CTD = (contemporary climate at the test site) – (historic climate at the seed source). ## Description of the variables The data set includes the survival and growth rates of 13 tropical montane cloud forest trees after eight years of planting across eight sites along an elevation gradient. Species codes CT = *Carpinus tropicalis* *CM = Clethra macrophylla* *FU = Fraxinus uhdei* *JP = Juglans pyriformis* *MV = Magnolia vovidesii* *MA = Meliosma alba* *OD = Ocotea disjuncta* *OM = Oreomunnea mexicana* *PR = Prunus rhamnoides* *QG = Quercus germana* *QS = Quercus sartorii* *SC = Sideroxylon contrerasii* *UM = Ulmus mexicana*   Survival 1 = alive 0 = dead   CTD = Climatic Transfer Distance CMD = Hargreave’s Climate Moisture Deficit MAT = mean annual temperature MAP = mean annual precipitation Tmin  and Tmax = maximum and minimum annual temperatures Height_T0 = Tree seedling initial height at planting time RGRh = Relative Growth Rate in height RGRd = Relative growth Rate in diameter null = data not available due to individual death. Units for variables are: RGRh (cm / year); RGRd (cm/y); MAT (°C); Tmax (°C); Tmin (°C); MAP (mm); CMD (mm).   ## Code/Software  The script for analysis of Survival and Growth in R can be found in the supplementary material of the publication: Toledo-Aceves, T., Sosa, V., Vásquez-Reyes, V., & Sáenz-Romero, C. (2025). Assisted migration of cloud forest trees: Unearthing the effects of climatic transfer distance. *Journal of Environmental Management*, *377*, 124591. [doi.org/10.1016/j.jenvman.2025.124591](https://doi.org/10.1016/j.jenvman.2025.124591 "Persistent link using digital object identifier") ## Sharing/Access information Links to other publicly accessible locations of the data: [https://doi.org/10.17871/TRY.50](https://doi.org/10.17871/TRY.50)