@article{nilsson_hodge_frampton_dvorak_bergh_2020, title={Growth and modulus of elasticity of pine species and hybrids three years after planting in South Africa}, volume={82}, ISSN={["2070-2639"]}, DOI={10.2989/20702620.2020.1733769}, abstractNote={Growth data and modulus of elasticity (MOE) of 11 different pine species and hybrids were examined at six sites in three regions in South Africa. Growth traits and three MOE variables were measured at three years of age in order to evaluate whether other potential pine species were more suitable than the current commercial species. There were strong observed species differences for all three MOE variables both within and across the four sites measured for wood properties, with across-site MOE ranging from 3.03 to 6.40 GPa. Green density varied among species, and an assumed constant green density of 1 000 kg m–3 underestimated MOE for species with a very high green density; similarly, for species with a very low green density, MOE was overestimated. Although survival was poor at several sites, the data shows that there are alternative pine species that exhibit comparable growth rates to the current commercial species. For estimating MOE, it is concluded that assuming a constant green density generally does not affect the species ranking, but if the aim is to find the ‘true’ MOE, sampling in the field to determine the appropriate green density is needed.}, number={4}, journal={SOUTHERN FORESTS}, author={Nilsson, O. and Hodge, G. R. and Frampton, L. J. and Dvorak, W. S. and Bergh, J.}, year={2020}, month={Nov}, pages={367–376} }
 @article{lopez_abt_dvorak_hodge_phillips_2018, title={Tree breeding model to assess financial performance of pine hybrids and pure species: deterministic and stochastic approaches for South Africa}, volume={49}, ISSN={["1573-5095"]}, DOI={10.1007/s11056-017-9609-1}, number={1}, journal={NEW FORESTS}, author={Lopez, Juan L. and Abt, Robert C. and Dvorak, William S. and Hodge, Gary R. and Phillips, Richard}, year={2018}, month={Jan}, pages={123–142} }
 @article{hodge_dvorak_2015, title={Provenance variation and within-provenance genetic parameters in Eucalyptus urophylla across 125 test sites in Brazil, Colombia, Mexico, South Africa and Venezuela}, volume={11}, ISSN={["1614-2950"]}, DOI={10.1007/s11295-015-0889-3}, number={3}, journal={TREE GENETICS & GENOMES}, author={Hodge, G. R. and Dvorak, W. S.}, year={2015}, month={Jun} }
 @misc{koskela_vinceti_dvorak_bush_dawson_loo_kjaer_navarro_padolina_bordacs_et al._2014, title={Utilization and transfer of forest genetic resources: A global review}, volume={333}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2014.07.017}, abstractNote={Over the last 200 years, genetic resources of forest trees have been increasingly transferred, within and outside of species’ native distribution ranges, for forestry and for research and development (R&D). Transferred germplasm has been deployed to grow trees for numerous purposes, ranging from the production of wood and non-wood products to the provision of ecosystem services such as the restoration of forests for biodiversity conservation. The oldest form of R&D, provenance trials, revealed early on that seed origin has a major influence on the performance of planted trees. International provenance trials have been essential for selecting seed sources for reforestation and for improving tree germplasm through breeding. Many tree breeding programmes were initiated in the 1950s, but as one round of testing and selection typically takes decades, the most advanced of them are only in their third cycle. Recent advances in forest genomics have increased the understanding of the genetic basis of different traits, but it is unlikely that molecular marker-assisted approaches will quickly replace traditional tree breeding methods. Furthermore, provenance trials and progeny tests are still needed to complement new research approaches. Currently, seed of boreal and temperate trees for reforestation purposes are largely obtained from improved sources. The situation is similar for fast growing tropical and subtropical trees grown in plantations, but in the case of tropical hardwoods and many agroforestry trees, only limited tested or improved seed sources are available. Transfers of tree germplasm involve some risks of spreading pests and diseases, of introducing invasive tree species and of polluting the genetic make-up of already present tree populations. Many of these risks have been underestimated in the past, but they are now better understood and managed. Relatively few tree species used for forestry have become invasive, and the risk of spreading pests and diseases while transferring seed is considerably lower than when moving live plants. The implementation of the Nagoya Protocol on access to genetic resources and benefit sharing (ABS) may significantly change current transfer practices in the forestry sector by increasing transaction costs and the time needed to lawfully obtain forest genetic resources for R&D purposes. Many countries are likely to struggle to establish a well-functioning ABS regulatory system, slowing down the process of obtaining the necessary documentation for exchange. This is unfortunate, as climate change, outbreaks of pests and diseases, and continual pressure to support productivity, increase the need for transferring tree germplasm and accelerating R&D.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Koskela, Jarkko and Vinceti, Barbara and Dvorak, William and Bush, David and Dawson, Ian K. and Loo, Judy and Kjaer, Erik Dahl and Navarro, Carlos and Padolina, Cenon and Bordacs, Sandor and et al.}, year={2014}, month={Dec}, pages={22–34} }
 @article{brawner_hodge_meder_dvorak_2014, title={Visualising the environmental preferences of Pinus tecunumanii populations}, volume={10}, ISSN={["1614-2950"]}, DOI={10.1007/s11295-014-0747-8}, abstractNote={A network of 92 pedigreed ex situ conservation plantings of Pinus tecunumanii, established as replicated progeny within provenance trials, is used to present a principal components-based analysis that illustrates the climatic preferences of 23 populations from the species’ native range. This meta-analysis quantifies changes in the relative productivity, assessed as individual-tree volume, of populations across climatic gradients and associates the preference of a population with increased volume production along the climatic gradient. Clustering and ordination on the matrix containing estimates of change in productivity for each population summarise differentials in productivity associated with climatic gradients. The preference of populations along principal components therefore reflects the adaptive profiles of populations, which may be used with breeding-value estimates from routine genetic evaluations to assist with the development of deployment populations targeting different environments. As well, the approach may be used to test whether the preference of a population, estimated as population loadings for growth differentials, is affected by the climate in the native range of the population. This relationship may be interpreted as an estimate of how much local climate shapes the adaptive profiles of populations. The amount and seasonality of precipitation most clearly differentiate the adaptive profiles of populations, with less variation in the population responses explained by temperature differentiation. As expected from type-B correlation estimates, most populations exhibited small changes in relative productivity across climatic gradients. However, patterns of similarities in adaptive profiles among populations were evident using spatial orientation to display population responses to the climatic variables experienced in the provenance trials. Clustering and ordination of population responses derived from empirical data served to identify populations that responded positively or negatively to climatic variables; this information may help guide conservation genetics efforts, direct the deployment of germplasm, or identify seed sources that are sensitive to changes in climatic variables. Linking response patterns to the climatic data from the native range of each population indicated little effect of local climate shaping adaptive profiles.}, number={5}, journal={TREE GENETICS & GENOMES}, author={Brawner, J. T. and Hodge, G. R. and Meder, R. and Dvorak, W. S.}, year={2014}, month={Oct}, pages={1123–1133} }
 @article{leibing_signer_zonneveld_jarvis_dvorak_2013, title={Selection of Provenances to Adapt Tropical Pine Forestry to Climate Change on the Basis of Climate Analogs}, volume={4}, ISSN={["1999-4907"]}, DOI={10.3390/f4010155}, abstractNote={Pinus patula and Pinus tecunumanii play an important role in the forestry sector in the tropics and subtropics and, in recent decades, members of the International Tree Breeding and Conservation Program (Camcore) at North Carolina State University have established large, multi-site provenance trials for these pine species. The data collected in these trials provide valuable information about species and provenance choice for plantation establishment in many regions with different climates. Since climate is changing rapidly, it may become increasingly difficult to choose the right species and provenance to plant. In this study, growth performance of plantings in Colombia, Brazil and South Africa was correlated to the degree of climatic dissimilarity between planting sites. Results are used to assess the suitability of seed material under a changing climate for four P. patula provenances and six P. tecunumanii provenances. For each provenance, climate dissimilarities based on standardized Euclidean distances were calculated and statistically related to growth performances. We evaluated the two methods of quantifying climate dissimilarity with extensive field data based on the goodness of fit and statistical significance of the climate distance relation to differences in height growth. The best method was then used as a predictor of a provenance change in height growth. The provenance-specific models were}, number={1}, journal={FORESTS}, author={Leibing, Christoph and Signer, Johannes and Zonneveld, Maarten and Jarvis, Andrew and Dvorak, William}, year={2013}, month={Mar}, pages={155–178} }
 @article{mitchell_wingfield_hodge_dvorak_coutinho_2013, title={Susceptibility of provenances and families of Pinus maximinoi and Pinus tecunumanii to frost in South Africa}, volume={44}, ISSN={["1573-5095"]}, DOI={10.1007/s11056-012-9306-z}, abstractNote={The future of South Africa's most important pine species, Pinus patula, is threatened by the pitch canker fungus, Fusarium circinatum. Pinus maximinoi and P. tecunumanii represent two subtropical species that provide an alternative to planting P. patula on the warmer sites of South Africa. Extending the planting range of P. tecunumanii and P. maximinoi to include higher and colder altitude sites will reduce the area planted to P. patula and the risk of F. circinatum. During 2007 progeny trials of P. tecunumanii and P. maximinoi were planted on a sub-tropical and sub-temperate site. Shortly after the establishment of these trials, unusually cold weather conditions were experienced across South Africa (−3°C at the sub-temperate site) resulting in severe mortality. This provided the opportunity to assess the variation in survival as a measure of frost tolerance within these two species to determine whether it could be improved upon through selection. Results indicated that the variation in survival was under genetic control in P. tecunumanii (h (0,1) 2 = 0.16, h L 2 = 0.27) and P. maximinoi (h (0,1) 2 = 0.11, h L 2 = 0.23) at the sub-temperate site. Correlations in provenance ranking for survival across sites were high for both species. Moderate correlations in family survival for P. tecunumanii (r = 0.52) were found at the two sites. Improvements in cold tolerance can thus be made in both species extending their planting range to include greater areas planted to P. patula thereby limiting the risk of F. circinatum.}, number={1}, journal={NEW FORESTS}, author={Mitchell, R. G. and Wingfield, M. J. and Hodge, G. R. and Dvorak, W. S. and Coutinho, T. A.}, year={2013}, month={Jan}, pages={135–146} }
 @article{hodge_dvorak_tighe_2012, title={Comparisons between laboratory and field results of frost tolerance of pines from the southern USA and Mesoamerica planted as exotics}, volume={74}, ISSN={["2070-2639"]}, DOI={10.2989/20702620.2012.683637}, abstractNote={An artificial freezing study was conducted with 14 pine species and varieties from Mexico and Central America, and the southern and western USA. The pines chosen represented major commercial plantation species in the Southern Hemisphere such as Pinus caribaea var. hondurensis, P. taeda (multiple sources), P. patula and P. radiata, as well as promising species such as P. greggii, P. maximinoi and P. tecunumanii. Seedlings were grown in environmentally controlled growth chambers in the North Carolina State University Phytotron, and conditions were designed to mimic actual climatic conditions at Curitiba, Brazil, and Sabie, South Africa, located at approximately 25° S latitude. Early autumn conditions were simulated using shortened photoperiods and lower temperatures to harden the trees before the actual freeze testing. There were two freeze experiments: one containing tropical and subtropical material using four temperature treatments (-3, -7, -10, and -14 °C), and one containing temperate and subtropical material using temperatures -7, -14, -21, and -28 °C. Needle segments were frozen, and damage assessed using the electrolyte leakage technique. Rankings of species, varieties and sources corresponded well with field results and expectations based on climate of the source origins. The rankings of pure species and varieties should be useful to predict frost tolerance of pine hybrids, and the methodology shows promise for future experiments to quantify cold tolerance and genetic variation among hybrid progeny.}, number={1}, journal={SOUTHERN FORESTS-A JOURNAL OF FOREST SCIENCE}, author={Hodge, G. R. and Dvorak, W. S. and Tighe, M. E.}, year={2012}, pages={7–17} }
 @article{wee_li_dvorak_hong_2012, title={Genetic diversity in natural populations of Gmelina arborea: implications for breeding and conservation}, volume={43}, ISSN={["0169-4286"]}, DOI={10.1007/s11056-011-9288-2}, number={4}, journal={NEW FORESTS}, author={Wee, Alison K. S. and Li, ChunHong and Dvorak, William S. and Hong, Yan}, year={2012}, month={Jul}, pages={411–428} }
 @article{hodge_dvorak_2012, title={Growth potential and genetic parameters of four Mesoamerican pines planted in the Southern Hemisphere}, volume={74}, ISSN={["2070-2639"]}, DOI={10.2989/20702620.2012.686192}, abstractNote={Summary results are reported from a total of 319 provenance/progeny tests of Pinus tecunumanii, P. maximinoi, P. patula and P. greggii that were established on sites in Brazil, Colombia and South Africa. Tests were measured for the growth traits height, diameter at breast height (DBH) and volume at ages 3, 5 and 8 years. At a particular age, correlations among height, DBH and volume were very high (from 0.80 to 0.99) at both the provenance and additive genetic levels, and the three growth traits also had similar heritabilities. Volume at age 3 was highly correlated with age 8 volume (around 0.80), and correlations of age 5 volume with age 8 volume were near 0.95. Low-elevation P. tecunumanii had very high between-country correlations both at the provenance and genetic level (around 0.80 to 1.00). Between-country genetic correlations for most other species were around 0.60. Two of the four species, P. tecunumanii and P. maximinoi, grew substantially faster than the commercial controls planted with the progeny tests (i.e. genetically improved P. taeda in Brazil, and improved P. patula in Colombia and South Africa). Pinus greggii var. australis also demonstrated commercial potential on sites in southern Brazil and South Africa. For all species, the best provenance produced 10–20% more volume than the population mean. In all species, additive genetic variation was substantial, and additional genetic gain could be made by family and within-family selection in an intensive tree-breeding effort.}, number={1}, journal={SOUTHERN FORESTS-A JOURNAL OF FOREST SCIENCE}, author={Hodge, G. R. and Dvorak, W. S.}, year={2012}, pages={27–49} }
 @article{espinoza_hodge_dvorak_2012, title={The potential use of near infrared spectroscopy to discriminate between different pine species and their hybrids}, volume={20}, ISSN={["1751-6552"]}, DOI={10.1255/jnirs.1006}, abstractNote={ There is growing interest in the use of pine hybrids in commercial forestry plantations in the tropics and sub-tropics. However, the production of pine hybrid seeds can be difficult and is dependent on the presence of an adequate number of male and female strobili, timely application of the pollination bag, good pollination techniques and reasonable weather conditions. After pollination, a wait of two or more years is required for cones to mature and for seeds to be collected. The seeds collected from artificial hybrid crosses in an orchard are assumed to be true hybrids, but might also be the (female) pure species if pollen contamination has occurred prior to or during bagging of the male strobili. Confirming hybridity in pines is often very difficult in the seedling stage when only needle morphological characteristics are used. In this study, we examined ground oven-dried needle samples of 16 pine species from different geographic regions using near infrared (NIR) spectroscopy to determine if this method is effective in distinguishing between pine species. We also created three “simulated hybrids” by manually mixing needles from three sets of parental pure species. The raw near infrared reflectance spectroscopy data were transformed using standard normal variate and de-trending techniques and a model was developed to distinguish between pure pine species and their “hybrids” using discriminant analysis. A total of 120 paired-species models were developed (one for each potential hybrid of the 16 species). For each of the 120 paired-species models, there were 20 independent observations in a validation data set and the 2400 observations were classified with 94% accuracy. Models were also developed for each of six species-simulated hybrid data sets. A total of 120 independent validation observations were classified as either parental species or simulated hybrid with 90% accuracy. The results indicate that NIR spectroscopy can be used as an effective tool to distinguish between pure pine species and suggest that it will also distinguish hybrids from their parents. Using NIR spectroscopy to verify hybridity in pines might be quicker and less expensive and, in some cases, as accurate as using molecular techniques. }, number={4}, journal={JOURNAL OF NEAR INFRARED SPECTROSCOPY}, author={Espinoza, Jesus A. and Hodge, Gary R. and Dvorak, William S.}, year={2012}, pages={437–447} }
 @article{dvorak_2012, title={The strategic importance of applied tree conservation programs to the forest industry in South Africa}, volume={74}, ISSN={["2070-2639"]}, DOI={10.2989/20702620.2012.683635}, abstractNote={Because of anticipated adverse climatic change and resulting increases in disease and insect attacks in forest plantations in the future, forest industries must maintain broad genetic bases for adaptability and pest resistance. Since the early 1980s, the South African forest industry has obtained genetic material of 25 pine and eucalypt species that represent more than 4 200 trees from 260 natural populations around the world through its participation in Camcore (International Tree Breeding and Conservation Program) at North Carolina State University, USA. This combined genetic testing and conservation program has identified new productive pine species, such as P. tecunumanii and P. maximinoi, that grow well and are resistant in the seedling stage to the pitch canker fungus (Fusarium circinatum). Because of the industry's foresight to assemble genetic material and test alternate species over the last three decades, it was well prepared to immediately develop more-resistant pine hybrids such as P. patula × P. tecunumanii when the pitch canker situation became problematic. The South African forest industry has collectively worked together to established special 20–40 ha conservation parks across the country to hold and protect the original genetic material collected in Central America, Mexico and South-east Asia. Species are conserved in the parks at the population level and are represented by a minimum of 10 open-pollinated families, five trees per family across two sites. The design is based on maintaining an effective population size of approximately 30 with the goal to capture alleles at high frequencies as well as to include a number of rare alleles in the ex situ plantings. The overlying goal is to maintain well-adapted genetic material for future deployment.}, number={1}, journal={SOUTHERN FORESTS-A JOURNAL OF FOREST SCIENCE}, author={Dvorak, Ws}, year={2012}, pages={1–6} }
 @article{dvorak_2012, title={Water use in plantations of eucalypts and pines: a discussion paper from a tree breeding perspective}, volume={14}, ISSN={["2053-7778"]}, DOI={10.1505/146554812799973118}, abstractNote={SUMMARY Plantation forests are being established on more marginal, harsh sites to accommodate expansion of agriculture. Because of this, tree breeders and silviculturists are interested in improving drought hardiness of trees. Breeding approaches to improve drought hardiness includes the assessment of trees as dead or alive in trials after severe droughts followed by the selection of the best surviving phenotypes for the establishment of seed orchards or land races. Physiologists estimate water utilization in trees in terms of water use efficiency (WUE). It is a function of biomass per unit of evapotranspiration and is calculated on a leaf or wood scale in clonal plots and stands. The gene complexes that control drought hardiness and WUE are probably different. It one respect, traditional breeding might have a limited impact on changing WUE since it will be difficult to alter rate of evapotranspiration through selection. In another respect, one could argue that selecting trees for high productivity is indirectly selecting for high WUE in some environments. Alternative approaches such as assessing heavy isotopes of carbon and oxygen in leaf tissue are being used by some scientists as a surrogate measure of water use in crops and trees. This paper presents the general findings from catchment studies on water uptake in pines and eucalypts and discusses how tree breeders might use results to further the development of drought hardy varieties grown in seasonally dry environments.}, number={1}, journal={INTERNATIONAL FORESTRY REVIEW}, author={Dvorak, W. S.}, year={2012}, pages={110–119} }
 @inproceedings{jetton_dvorak_potter_whittier_rhea_2011, title={Genetics and conservation of hemlock species threatened by the hemlock woolly adelgid}, booktitle={Proceedings of the 30th Southern Tree Improvement Conference}, author={Jetton, R. M. and Dvorak, W.S. and Potter, K. M. and Whittier, W. A. and Rhea, J.}, year={2011}, pages={81–87} }
 @article{potter_jetton_dvorak_hipkins_rhea_whittier_2011, title={Widespread inbreeding and unexpected geographic patterns of genetic variation in eastern hemlock (Tsuga canadensis), an imperiled North American conifer}, volume={13}, ISSN={1566-0621 1572-9737}, url={http://dx.doi.org/10.1007/s10592-011-0301-2}, DOI={10.1007/s10592-011-0301-2}, abstractNote={Eastern hemlock (Tsuga canadensis [L.] Carr.) is an ecologically important tree species experiencing severe mortality across much of its eastern North American distribution, caused by infestation of the exotic hemlock woolly adelgid (Adelges tsugae Annand). To guide gene conservation strategies for this imperiled conifer, we conducted a range-wide genetic variation study for eastern hemlock, amplifying 13 highly polymorphic nuclear microsatellite loci in 1,180 trees across 60 populations. The results demonstrate that eastern hemlock exhibits moderate inbreeding, possibly a signature of a prehistoric decline associated with a widespread insect outbreak. Contrary to expectations, populations in formerly glaciated regions are not less genetically diverse than in the putative southern refugial region. As expected, peripheral disjunct populations are less genetically diverse than main-range populations, but some are highly genetically differentiated or contain unique alleles. Spatially explicit Bayesian clustering analyses suggest that three or four Pleistocene glacial refuges may have existed in the Southeastern United States, with a main post-glacial movement into the Northeast and the Great Lakes region. Efforts to conserve eastern hemlock genetic material should emphasize the capture of broad adaptability that occurs across the geographic range of the species, as well as genetic variability within regions with the highest allelic richness and heterozygosity, such as the Southern Appalachians and New England, and within disjunct populations that are genetically distinct. Much genetic variation exists in areas both infested and uninfested by the adelgid.}, number={2}, journal={Conservation Genetics}, publisher={Springer Nature}, author={Potter, Kevin M. and Jetton, Robert M. and Dvorak, William S. and Hipkins, Valerie D. and Rhea, Rusty and Whittier, W. Andrew}, year={2011}, month={Dec}, pages={475–498} }
 @inproceedings{potter_jetton_dvorak_frampton_rhea_2010, title={Ex situ seed collection represents genetic variation present in natural stands of Carolina hemlock}, booktitle={Proceedings of the Fifth Symposium on Hemlock Woolly Adelgid in the Eastern United States}, author={Potter, K.M. and Jetton, R.M. and Dvorak, W.S. and Frampton, J. and Rhea, J.}, year={2010}, pages={181–190} }
 @article{leibing_zonneveld_jarvis_dvorak_2009, title={Adaptation of tropical and subtropical pine plantation forestry to climate change: Realignment of Pinus patula and Pinus tecunumanii genotypes to 2020 planting site climates}, volume={24}, ISSN={["1651-1891"]}, DOI={10.1080/02827580903378642}, abstractNote={Abstract Pinus patula and Pinus tecunumanii, two pines native to Mexico and Central America, are important plantation species for the forestry sector in the tropics and subtropics. In recent decades, members of the International Tree Conservation & Domestication Program (CAMCORE), North Carolina State University, have established large, multisite provenance trials for these pine species. The data provide valuable information about species and provenance choice for plantation establishment in many regions with different climates. However, since climate is changing rapidly, it may become increasingly difficult to choose the right species and provenance to plant. The aim of this study is to test the suitability of seed material under changing climate of two P. patula varieties (P. patula var. patula and P. patula var. longipedunculata) and two P. tecunumanii ecotypes (highland and lowland). For each variety and ecotype, a site quality model was developed that statistically relates growth to environmental factors and couples the predictions to the average 2020 climate prediction of four general circulation models. Three developed models were significant and robust. Provenances of P. tecunumanii from lowland areas in Central America are expected to be most productive in 2020 because of their promising performance under rather hot and wet climates.}, number={6}, journal={SCANDINAVIAN JOURNAL OF FOREST RESEARCH}, author={Leibing, Christoph and Zonneveld, Maarten and Jarvis, Andrew and Dvorak, William}, year={2009}, pages={483–493} }
 @article{zonneveld_jarvis_dvorak_lema_leibing_2009, title={Climate change impact predictions on Pinus patula and Pinus tecunumanii populations in Mexico and Central America}, volume={257}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2008.12.027}, abstractNote={Climate change is likely to have a negative impact on natural populations of Pinus patula and Pinus tecunumanii, two globally important tree species in plantation forestry. The objective of this work was to evaluate the impact of climate change on the persistence of the natural populations of these species at their actual locations in order to take appropriate conservation measurements. A common approach to assess the impact of climate change on species natural distributions is climate envelope modeling (CEM). CEMs suggest significant impacts of climate change on the natural distribution of the two pine species, but their predictions contain considerable uncertainty related to the adaptive ability of tree populations to withstand future climate conditions. We assessed the adaptive ability of the two pine species based on the evaluations of provenance trials and used the results of these field trials to validate CEM impact assessment studies on provenance collection sites in the wild. The two pine species performed well in a wide range of climates, including conditions that were recorded by CEM as unsuitable for natural pine occurrence. The climate conditions where the two pine species naturally occur are predicted to become in the future more similar to the present climate of some areas where they are successfully established in field trials. These findings suggest that these pine species are in their natural habitat better adapted to climate change than CEM predicts. For the most vulnerable species, P. tecunumanii, human disturbances such as fragmentation from urbanization and conversion to agriculture that are occurring today are more urgent threats requiring action compared to the threat from climate change.}, number={7}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Zonneveld, Maarten and Jarvis, Andy and Dvorak, William and Lema, German and Leibing, Christoph}, year={2009}, month={Mar}, pages={1566–1576} }
 @inbook{mullin_andersson_bastien_beaulieu_burdon_dvorak_king_kondo_krakowski_lee_et al._2009, title={Economic importance, breeding objectives and achievements}, booktitle={Genomics of industrial crops}, publisher={New Hampshire, UK: Science Publishers}, author={Mullin, T. J. and Andersson, B. and Bastien, J.-C. and Beaulieu, J. and Burdon, R. D. and Dvorak, W. S. and King, J. N. and Kondo, T. and Krakowski, J. and Lee, S. D. and et al.}, editor={Plomion, C. and Bousquet, J.Editors}, year={2009} }
 @article{dvorak_potter_hipkins_hodge_2009, title={Genetic Diversity and Gene Exchange in Pinus oocarpa, a Mesoamerican Pine with Resistance to the Pitch Canker Fungus (Fusarium circinatum)}, volume={170}, ISSN={1058-5893 1537-5315}, url={http://dx.doi.org/10.1086/597780}, DOI={10.1086/597780}, abstractNote={Eleven highly polymorphic microsatellite markers were used to determine the genetic structure and levels of diversity in 51 natural populations of Pinus oocarpa across its geographic range of 3000 km in Mesoamerica. The study also included 17 populations of Pinus patula and Pinus tecunumanii chosen for their resistance or susceptibility to the pitch canker fungus based on previous research. Seedlings from all 68 populations were screened for pitch canker resistance, and results were correlated to mean genetic diversity and collection site variables. Results indicate that P. oocarpa exhibits average to above‐average levels of genetic diversity (
\documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage[OT2,OT1]{fontenc}
\newcommand\cyr{
\renewcommand\rmdefault{wncyr}
\renewcommand\sfdefault{wncyss}
\renewcommand\encodingdefault{OT2}
\normalfont
\selectfont}
\DeclareTextFontCommand{\textcyr}{\cyr}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
\landscape
$$A=19.82$$
\end{document} , 
\documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage[OT2,OT1]{fontenc}
\newcommand\cyr{
\renewcommand\rmdefault{wncyr}
\renewcommand\sfdefault{wncyss}
\renewcommand\encodingdefault{OT2}
\normalfont
\selectfont}
\DeclareTextFontCommand{\textcyr}{\cyr}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
\landscape
$$A_{\mathrm{R}\,}=11.86$$
\end{document} , 
\documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage[OT2,OT1]{fontenc}
\newcommand\cyr{
\renewcommand\rmdefault{wncyr}
\renewcommand\sfdefault{wncyss}
\renewcommand\encodingdefault{OT2}
\normalfont
\selectfont}
\DeclareTextFontCommand{\textcyr}{\cyr}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
\landscape
$$H_{\mathrm{E}\,}=0.711$$
\end{document} ) relative to other conifers. Most populations were out of Hardy‐Weinberg equilibrium, and a high degree of inbreeding was found in the species (
\documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage[OT2,OT1]{fontenc}
\newcommand\cyr{
\renewcommand\rmdefault{wncyr}
\renewcommand\sfdefault{wncyss}
\renewcommand\encodingdefault{OT2}
\normalfont
\selectfont}
\DeclareTextFontCommand{\textcyr}{\cyr}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
\landscape
$$F_{\mathrm{IS}\,}=0.150$$
\end{document} ). Bayesian analysis grouped P. oocarpa into four genetic clusters highly correlated to geography and distinct from P. patula and P. tecunumanii. Historic gene flow across P. oocarpa clusters was observed (
\documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage[OT2,OT1]{fontenc}
\newcommand\cyr{
\renewcommand\rmdefault{wncyr}
\renewcommand\sfdefault{wncyss}
\renewcommand\encodingdefault{OT2}
\normalfont
\selectfont}
\DeclareTextFontCommand{\textcyr}{\cyr}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
\landscape
$$N_{\mathrm{m}\,}=1.1{\mbox{--}} 2.7$$
\end{document} ), but the most pronounced values were found between P. oocarpa and P. tecunumanii (low‐altitude provenances) in Central America (
\documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage[OT2,OT1]{fontenc}
\newcommand\cyr{
\renewcommand\rmdefault{wncyr}
\renewcommand\sfdefault{wncyss}
\renewcommand\encodingdefault{OT2}
\normalfont
\selectfont}
\DeclareTextFontCommand{\textcyr}{\cyr}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
\landscape
$$N_{\mathrm{m}\,}=9.7$$
\end{document} ). Pinus oocarpa appears to have two main centers of diversity, one in the Eje Transversal Volcánico in central Mexico and the other in Central America. Introgression between P. oocarpa and P. tecunumanii populations appears to be common. Pinus oocarpa populations showed high resistance to pitch canker (stemkill 3%–8%), a disease that the species has presumably coevolved with in Mesoamerica. Resistance was significantly correlated to the latitude, longitude, and altitude of the collection site but not to any genetic‐diversity parameters or degree of admixture with P. tecunumanii.}, number={5}, journal={International Journal of Plant Sciences}, publisher={University of Chicago Press}, author={Dvorak, W. S. and Potter, K. M. and Hipkins, V. D. and Hodge, G. R.}, year={2009}, month={Jun}, pages={609–626} }
 @inproceedings{jetton_dvorak_whittier_potter_2009, title={Genetics and conservation of hemlock species threatened by the hemlock woolly adelgid}, booktitle={Proceedings of the 20th U.S. Department of Agriculture Interagency Research Forum on Invasive Species}, author={Jetton, R.M. and Dvorak, W.S. and Whittier, W.A. and Potter, K.M.}, year={2009}, pages={39–40} }
 @misc{jetton_dvorak_whittier_2008, title={Ecological and genetic factors that define the natural distribution of Carolina hemlock in the southeastern United States and their role in ex situ conservation}, volume={255}, ISSN={["0378-1127"]}, DOI={10.1016/j.foreco.2008.01.032}, abstractNote={Carolina hemlock (Tsuga caroliniana Engelm.) is a rare endemic found in the Appalachian Mountains and Upper Piedmont of the southeastern United States. It is being decimated by the hemlock woolly adelgid (Adelges tsugae Annand), an exotic pest introduced into the region from Japan several decades ago. We examine ecological, genetic and climatic factors in natural stands that characterize the species’ occurrence to better determine where ex situ conservation plantings should be established. To facilitate species/site matching, we use FloraMap™ software that quantifies climatic variables at provenance collection sites to predict other areas where Carolina hemlock could be planted in the U.S. and Latin America. Results indicate that based on analysis of 15 populations, Carolina hemlock is found on predominantly sandy-clay loam soils but occurs on a wider range of soil textural groups than previously thought. Its natural occurrence represents two different climatic groups, with the Cradle of Forestry, NC site most different than the rest. FloraMap™ predicts with high probability that Carolina hemlock populations can be successfully moved to central Chile, and with lower probability to the Ozark region of Arkansas and southern Brazil. Camcore, North Carolina State University, has now collected seeds from 12 provenances and 77 mother trees in natural populations of Carolina hemlock and distributed these to the three regions listed above. Our goal is to sample 150 trees from the 15 provenances which will sample most of the species’ genetic diversity for ex situ conservation. The ex situ approach offers an alternate means of protecting the species if efforts to control the adelgid fail in the southeastern US.}, number={8-9}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Jetton, Robert M. and Dvorak, William S. and Whittier, W. Andrew}, year={2008}, month={May}, pages={3212–3221} }
 @article{dvorak_2008, title={Estamos mas cerca de entender la ascendencia de las poblaciones de la ?variante patula? en la Sierra Madre del sur, Mexico?}, volume={10}, number={1}, journal={Foresta Veracruzana}, author={Dvorak, W. S.}, year={2008}, pages={59–66} }
 @article{jetton_hain_dvorak_frampton_2008, title={Infestation Rate of Hemlock Woolly Adelgid (Hemiptera: Adelgidae) Among Three North American Hemlock (Tsuga) Species Following Artificial Inoculation}, volume={43}, ISSN={["0749-8004"]}, DOI={10.18474/0749-8004-43.4.438}, number={4}, journal={JOURNAL OF ENTOMOLOGICAL SCIENCE}, author={Jetton, Robert M. and Hain, Fred P. and Dvorak, William S. and Frampton, John}, year={2008}, month={Oct}, pages={438–442} }
 @article{payn_dvorak_janse_myburg_2008, title={Microsatellite diversity and genetic structure of the commercially important tropical tree species Eucalyptus urophylla, endemic to seven islands in eastern Indonesia}, volume={4}, ISSN={["1614-2950"]}, DOI={10.1007/s11295-007-0128-7}, number={3}, journal={TREE GENETICS & GENOMES}, author={Payn, Kitt G. and Dvorak, William S. and Janse, Bernard J. H. and Myburg, Alexander A.}, year={2008}, month={Jul}, pages={519–530} }
 @inproceedings{jetton_whittier_dvorak_potter_2008, title={Status of ex situ conservation efforts for eastern and Carolina hemlock in the southeastern United States}, booktitle={Proceedings of the 4th Symposium on Hemlock Woolly Adelgid}, author={Jetton, R.M. and Whittier, W.A. and Dvorak, W.S. and Potter, K.M.}, year={2008}, pages={81–89} }
 @article{dvorak_hodge_payn_2008, title={The conservation and breeding of Eucalyptus urophylla: a case study to better protect important populations and improve productivity}, volume={70}, ISSN={["2070-2639"]}, DOI={10.2989/south.for.2008.70.2.3.531}, abstractNote={Eucalyptus urophylla is one of the most commercially important forest species in the world, primarily as a hybrid parent. However, the conservation status of the majority of the populations where it naturally occurs on seven islands in eastern Indonesia range from critically endangered to vulnerable. We examine the evolutionary forces that might have caused genetic variation within and between E. urophylla populations and link these findings to international provenance trial results and molecular marker studies. We demonstrate that one climatic type does not describe all E. urophylla populations. We suggest that volcanism played an important role in its distribution and levels of genetic diversity on the islands. We report significant provenance variation for survival and growth in trials established in Brazil, Colombia, Mexico, South Africa and Venezuela. Provenance differences for growth within a country are sometimes >50%. Based on these assessments, we develop an ex situ conservation strategy to protect populations that are most threatened but also show the greatest productivity across countries. We conclude that populations of E. urophylla will only be conserved ex situ if traditional and molecular tree breeders convince private industry of the economic importance to do so.}, number={2}, journal={SOUTHERN FORESTS-A JOURNAL OF FOREST SCIENCE}, author={Dvorak, W. S. and Hodge, G. R. and Payn, K. G.}, year={2008}, month={Aug}, pages={77–85} }
 @article{potter_dvorak_crane_hipkins_jetton_whittier_rhea_2007, title={Allozyme variation and recent evolutionary history of eastern hemlock (Tsuga canadensis) in the southeastern United States}, volume={35}, ISSN={0169-4286 1573-5095}, url={http://dx.doi.org/10.1007/s11056-007-9067-2}, DOI={10.1007/s11056-007-9067-2}, abstractNote={Eastern hemlock (Tsuga canadensis [L.] Carr.) is a widespread and ecologically important conifer species of eastern North America that is threatened by the hemlock woolly adelgid (Adelges tsugae Annand), a pest introduced into the United States from Asia in the 1920s. Information about the genetic composition of eastern hemlock is necessary to guide ex situ conservation efforts in the southeastern United States, where the species is expected to harbor relatively high amounts of genetic variation in areas of Pleistocene glacial refuge. Nineteen allozyme markers were used to quantify the genetic variation present in 20 eastern hemlock populations in the southeastern United States. Results indicate that the species has low levels of genetic diversity in the region compared to most other conifers, but greater population differentiation (F ST = 0.126). Populations along the eastern periphery and in the Appalachian interior exhibited higher levels of diversity than those along the western periphery of its geographic range. The results suggest that the glacial refuge area for eastern hemlock was likely located east of the southern Appalachian Mountains, and indicate that ex situ conservation seed collections should be concentrated in these areas of higher diversity.}, number={2}, journal={New Forests}, publisher={Springer Nature}, author={Potter, K. M. and Dvorak, W. S. and Crane, B. S. and Hipkins, V. D. and Jetton, R. M. and Whittier, W. A. and Rhea, R.}, year={2007}, month={Oct}, pages={131–145} }
 @article{dvorak_kietzka_hodge_nel_santos_gantz_2007, title={Assessing the potential of Pinus herrerae as a plantation species for the subtropics}, volume={242}, ISSN={["0378-1127"]}, DOI={10.1016/j.foreco.2007.01.076}, abstractNote={Abstract Pinus herrerae Martinez is a little known hard pine that occurs in the western mountain ranges of Mexico between 16° and 28°N latitude and 1800 m and 2400 m altitude. Seed collections were made from 12 of the 14 populations that were identified through explorations and seedlings were established in either species, species/provenance, provenance/progeny trials or arboreta plantings in Brazil, Chile, Colombia and South Africa. Productivity of P. herrerae in 13 field trials ranged from 3 to 24 m 3 /ha/year (overbark), assessed at between 8 and 13 years. P. herrerae from temperate areas in Mexico is best adapted to cool dry areas in South Africa where minimum nighttime winter temperatures range −5 °C to 7 °C. Provenances of P. herrerae from subtropical regions in Mexico grew well in areas of similar climate in Brazil, Colombia, and South Africa where frosts seldom occurs. P. herrerae exhibited good stem form in most trials but growth of temperate sources was not comparable to that of P. patula , P. radiata or P. taeda , even when differences due to levels of genetic improvement were considered. The subtropical source of P. herrerae from Oaxaca (Juquila) grew as well as average unimproved sources of P. tecunumanii from Chiapas, Mexico when planted on appropriate sites in trials in Brazil, Colombia, and South Africa. Within provenance heritability ( h 2 ) for height and diameter of P. herrerae ranged from 0.08 to 0.14 in South Africa and from 0.44 to 0.46 in Brazil in two orthogonal trials. Heritability values for forking were 0.10 and 0.06 at each location, respectively. The ecological niche for P. herrerae as an exotic plantation species appears to climatically fall between (and often overlap with) areas that are currently being commercially planted to subtemperate species like P. greggii var. australis and the subtropical species P. tecunumanii .}, number={2-3}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Dvorak, W. S. and Kietzka, Eric and Hodge, G. R. and Nel, A. and Santos, G. A. and Gantz, C.}, year={2007}, month={Apr}, pages={598–605} }
 @article{payn_dvorak_myburg_2007, title={Chloroplast DNA phylogeography reveals the island colonisation route of Eucalyptus urophylla (Myrtaceae)}, volume={55}, ISSN={0067-1924}, url={http://dx.doi.org/10.1071/bt07056}, DOI={10.1071/BT07056}, abstractNote={We present a study of the colonisation patterns of a tropical tree species among an island archipelago. Eucalyptus urophylla (S.T.Blake) is an economically important plantation species endemic to the volcanic slopes of seven islands in eastern Indonesia. In the present study, we investigated the geographical distribution of chloroplast DNA sequence variation in E. urophylla to gain insight into its historical seed-migration routes. DNA sequence data were obtained from 198 plants from which 20 haplotypes were identified. A moderate to high level of chloroplast genetic differentiation (GST = 0.581, NST = 0.724) and significant phylogeographic structure (NST > GST; P < 0.01) were observed, suggesting low levels of recurrent seed-mediated gene flow among the islands. The highest levels of haplotype diversity were observed on the eastern islands of Wetar and Timor. The two most westerly islands, Flores and Lomblen, were fixed for what appeared to be the ancestral haplotype. Chloroplast haplotype diversity therefore exhibited a decreasing trend from east to west in the species’ range, consistent with an east-to-west colonisation route across the seven islands. Environmental factors that may have contributed to the contemporary spatial distribution of chloroplast DNA haplotypes include island paleogeology, ocean currents, fluctuations in sea levels and possible hybridisation events.}, number={7}, journal={Australian Journal of Botany}, publisher={CSIRO Publishing}, author={Payn, Kitt G. and Dvorak, William S. and Myburg, Alexander A.}, year={2007}, pages={673} }
 @article{dvorak_hodge_kietzka_2007, title={Genetic variation in survival, growth, and stem form of Pinus leiophylla in Brazil and South Africa and provenance resistance to pitch canker}, volume={69}, ISSN={["1991-9328"]}, DOI={10.2989/SHFJ.2007.69.3.1.351}, abstractNote={Pinus leiophylla is a relatively common pine that occurs in the mountains of western and central Mexico. Between 1987 and 1990, Camcore, North Carolina State University, sampled 11 populations and 309 mother trees of the species to determine patterns of genetic variation in survival, growth and stem form. Fifteen provenance/progeny trials were established in southern Brazil and South Africa across a wide range of sites and assessed at 3, 5 and 8 years of age for height, diameter and stem form. Results indicated that average productivity ranged from 5 to 19m3 ha−1 y−1 depending on the site and that performance was not as competitive as P. patula (South Africa) and P. taeda (Brazil) controls. Provenances from central Mexico (Michoacán) were statistically better in productivity than those from the southern part of the country (Oaxaca), which in turn were superior to those from the northern part of the country (Durango). However, provenances from northern Mexico exhibited superior survival to seed sources from other locations in Mexico when grown on cold sites (winter minimums –10 to 5°C) in South Africa and superior stem form across all locations. Seedlings from the original 11 provenances were screened for resistance to the pitch canker fungus (PCF; Fusarium circinatum). Results indicated that generally P. leiophylla is as susceptible to PCF as P. patula (stemkill = 85%) with the exception of two fast-growing, moderately resistant populations from Michoacán, La Pinalosa (stemkill = 44%) and Ario de Rosales (stemkill = 73%). The future potential of P. leiophylla might be in hybrid combination with P. patula in the seasonally dry areas of southern Africa where fires are common and pitch canker is a problem.}, number={3}, journal={SOUTHERN HEMISPHERE FORESTRY JOURNAL}, author={Dvorak, W. S. and Hodge, G. R. and Kietzka, J. E.}, year={2007}, month={Dec}, pages={125–135} }
 @article{hodge_dvorak_2007, title={Variation in pitch canker resistance among provenances of Pinus patula and Pinus tecunumanii from Mexico and Central America}, volume={33}, ISSN={["1573-5095"]}, DOI={10.1007/s11056-006-9023-6}, number={2}, journal={NEW FORESTS}, author={Hodge, G. R. and Dvorak, W. S.}, year={2007}, month={Mar}, pages={193–206} }
 @article{dvorak_hamrick_gutierrez_2005, title={The origin of Caribbean pine in the seasonal swamps of the Yucatan}, volume={166}, ISSN={["1537-5315"]}, DOI={10.1086/449314}, abstractNote={An isolated 180‐ha stand of Pinus caribaea var. hondurensis (Caribbean pine) exists at El Pinal, Guatemala, in seasonal marshlands 18 km northeast of the old Mayan capital city of Tikal. One hypothesis suggests that during the zenith of their culture between 600 and 900 AD, the Mayans planted the pine stand as a source of resinous lighter wood (ocote) to start cooking fires. We examine the alternate hypothesis that El Pinal is of natural origin. Allozyme analyses were used to compare genetic diversity levels at El Pinal with seven neighboring natural stands of Caribbean pine in Belize and Guatemala. Results indicated that the El Pinal population had a high proportion of polymorphic loci (88%), had four unique alleles, exhibited an outcrossing rate of 91%, and differed little from larger natural populations of Caribbean pine located 65–100 km away. Only 2.3% of the total genetic diversity (GST) was found among the eight populations, which suggests high historic levels of gene flow. A climatic model (FloraMap) that used data from 36 known pine provenances of Caribbean pine to predict the distribution of new populations examined differences between current and predicted geographic ranges of the species. The model predicted that Caribbean pine should occur (
\documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage[OT2,OT1]{fontenc}
\newcommand\cyr{
\renewcommand\rmdefault{wncyr}
\renewcommand\sfdefault{wncyss}
\renewcommand\encodingdefault{OT2}
\normalfont
\selectfont}
\DeclareTextFontCommand{\textcyr}{\cyr}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
\landscape
$$P> 40\% $$
\end{document} ) along the east coast of the Yucatán as far north as Puerto Juarez, Quintana Roo, Mexico, where it does not exist today. Genetic analyses indicate that El Pinal represents a population of ancient origin, and the climatic model indicates that El Pinal might have belonged to a larger historic distribution of Caribbean pine that occurred in the Yucatán when climates were drier than today.}, number={6}, journal={INTERNATIONAL JOURNAL OF PLANT SCIENCES}, author={Dvorak, WS and Hamrick, JL and Gutierrez, EA}, year={2005}, month={Nov}, pages={985–994} }
 @article{hodge_dvorak_2004, title={The CAMCORE international provenance/progeny trials of Gmelina arborea: genetic parameters and potential}, volume={28}, ISSN={["1573-5095"]}, DOI={10.1023/B:NEFO.0000040942.34566.a7}, number={2-3}, journal={NEW FORESTS}, author={Hodge, GR and Dvorak, WS}, year={2004}, month={Sep}, pages={147–166} }
 @article{dvorak_2004, title={World view of Gmelina arborea: opportunities and challenges}, volume={28}, ISSN={["1573-5095"]}, DOI={10.1023/B:NEFO.0000040940.32574.22}, number={2-3}, journal={NEW FORESTS}, author={Dvorak, WS}, year={2004}, month={Sep}, pages={111–126} }
 @article{dvorak_hodge_billingham_boshier_2003, title={Genetic variation in Bombacopsis quinata [Pachira quinata] and its use / Variacion genetica en Bombacopsis quinata y su uso}, ISBN={0850741513}, journal={Bombacopsis quinata : un a?rbol maderable para reforestar}, publisher={Oxford, U.K. : Oxford Forestry Institute}, author={Dvorak, W. S. and Hodge, G. R. and Billingham, M. R. and Boshier, D. H.}, editor={J. Cordero and Boshier, D.Editors}, year={2003} }
 @article{dvorak_hamrick_furman_hodge_jordan_2002, title={Conservation strategies for Pinus maximinoi based on provenance, RAPD and allozyme information}, volume={9}, ISBN={1335-048x}, number={4}, journal={Forest Genetics}, author={Dvorak, W. S. and Hamrick, J. L. and Furman, B. J. and Hodge, G. R. and Jordan, A. P.}, year={2002}, pages={263} }
 @article{hodge_dvorak_uruena_rosales_2002, title={Growth, provenance effects and genetic variation of Bombacopsis quinata in field tests in Venezuela and Colombia}, volume={158}, ISSN={["0378-1127"]}, DOI={10.1016/s0378-1127(00)00720-9}, abstractNote={Ten provenance/progeny tests of Bombacopsis quinata were established in Venezuela and Colombia using open-pollinated (OP) seed collected from throughout its natural range. In addition, two full-sib progeny tests were established in Colombia with seed from crosses made in a second-generation seed orchard. Average survival of all tests was approximately 80%, with the local source from Colombia (Atlántico) having slightly better survival in Colombia. Average growth rates at age 8 years were 6–7 m height and 12–13 cm DBH. Provenance×country interaction was highly significant between Colombia and Venezuela, although at a within-provenance level, families performed relatively consistently in the two countries (rBg=0.58). There was no important genotype×environment interaction at the provenance or family level between test sites in the same country. There were large provenance effects in both countries. In Colombia, two provenances from Nicaragua (Hacienda San Juan and Los Playones) performed as well as the local source, with 11–16% more volume than average. In Venezuela, provenances originating in areas of 1600–2100 mm of annual rainfall (Choluteca, Honduras, and Guanacaste, Costa Rica) had volumes 26% above average, while the local source performed poorly both in survival and growth. Heritabilities for growth traits are moderate and increase with age up to 0.25–0.30 at age 8 years. Dominance variance is relatively unimportant as it is approximately 14 or less than the size of additive variance. After the appropriate provenances have been identified, additional genetic gains of up to 50% in volume are possible from family and within family selection.}, number={1-3}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Hodge, GR and Dvorak, WS and Uruena, H and Rosales, L}, year={2002}, month={Mar}, pages={273–289} }
 @article{newton_allnutt_dvorak_del castillo_ennos_2002, title={Patterns of genetic variation in Pinus chiapensis, a threatened Mexican pine, detected by RAPD and mitochondrial DNA RFLP markers}, volume={89}, ISSN={["0018-067X"]}, DOI={10.1038/sj.hdy.6800113}, abstractNote={Pinus chiapensis (Pinaceae) is a large conifer, endemic to central and southern Mexico and north-western Guatemala. In order to assess the extent of genetic variation within and between populations of this species, samples were obtained from throughout the natural range and analysed using random amplified polymorphic DNA (RAPD) and mtDNA RFLPs markers. Probes for the CoxI mitochondrial gene enabled two mitotypes to be observed. Populations from the eastern and western limit of the range of the species were fixed for one mitotype ('A'), whereas two populations distributed near the centre of the range were fixed for another ('B'). When the samples were screened with eight 10-mer RAPD primers, a total of 12 polymorphic bands were detected. The proportion of polymorphic bands was unusually low (24.5%) compared with other tree species. AMOVA analysis indicated that a significant proportion of the variation (P < 0.002) was distributed between populations; the extent of population differentiation detected (Phi(st) = 0.226; G(ST ) = 0.194) was exceptionally high for a pine species. Pair-wise comparison of Phi(st) values derived from AMOVA indicated that populations were significantly (P < 0.05) different from each other in virtually every case. These results are interpreted in the context of the evolutionary history of the species, and the implications for its in- and ex situ conservation are discussed.}, journal={HEREDITY}, author={Newton, AC and Allnutt, TR and Dvorak, WS and Del Castillo, RF and Ennos, RA}, year={2002}, month={Sep}, pages={191–198} }
 @article{hodge_dvorak_2001, title={Genetic parameters and provenenance variation of Pinus caribaea var. hondurensis in 48 international trials}, volume={31}, ISSN={["0045-5067"]}, DOI={10.1139/cjfr-31-3-496}, number={3}, journal={CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE}, author={Hodge, GR and Dvorak, WS}, year={2001}, month={Mar}, pages={496–511} }
 @article{dvorak_2001, title={Positioning tree improvement programs to utilize advances in new technologies}, ISBN={0038-2167}, DOI={10.1080/20702620.2001.10434111}, abstractNote={Abstract Forestry will be characterized by many changes in early part of the 21st century. Forest industries will continue to merge in order to capture greater percentages ofthe woodand paper market. For example, iflnternational Paper Company acquires Champion International Corporation the new group will control 19% of the North American coated paper market (Pulp & Paper Week, 2000). Success of such business transactions will be determined by the returns on shareholder investments. With the merger of industries will come the realignment of research departments including tree improvement programs. Their cost effectiveness will come under even greater scrutiny than before. Forest biotechnology will continue to develop and much money will be invested in programs by the private sector, governmental agencies and universities. Molecular markers for indirect selection of quantitative trait loci (QTL) will continue to be important but the field of biotechnology will advance to identify the genes that directly control trait expression. Advances will also be made in wood utilization. Reconstituted lumber made of veneers, wood chips, or finger-jointed sections will capture more of the solid wood market. Forest biotechnologists will further their collaboration with wood chemists to better understand the lignin synthesis biopathways and greater emphasis will be given to identifying genes that control traits like cell wall thickness and the expression of juvenile and mature woodin trees. There will be important breakthroughs in biotechnology especially for traits like disease and herbicide resistance controlled by single genes. Traits governed by multiple gene complexes will be much more difficult to manipulate because of their complexity and any breakthroughs that develop will come under the scrutiny of an ever-suspicious public.}, number={190}, journal={Southern African Forestry Journal}, author={Dvorak, W. S.}, year={2001}, pages={19} }
 @article{dvorak_jordon_hodge_romero_2000, title={Assessing evolutionary relationships of pines in the Oocarpae and Australes subsections using RAPD markers}, volume={20}, ISSN={["1573-5095"]}, DOI={10.1023/A:1006763120982}, number={2}, journal={NEW FORESTS}, author={Dvorak, WS and Jordon, AP and Hodge, GP and Romero, JL}, year={2000}, month={Sep}, pages={163–192} }
 @book{conservation and testing of tropical and subtropical forest tree species by the camcore cooperative_2000, ISBN={0620264608}, publisher={Botha Hill, South Africa : Grow Graphics}, year={2000} }
 @article{hodge_dvorak_2000, title={Differential responses of Central American and Mexican pine species and Pinus radiata to infection by the pitch canker fungus}, volume={19}, ISSN={["1573-5095"]}, DOI={10.1023/A:1006613021996}, number={3}, journal={NEW FORESTS}, author={Hodge, GR and Dvorak, WS}, year={2000}, month={May}, pages={241–258} }
 @article{hall_dvorak_johnston_price_williams_2000, title={Flow cytometric analysis of DNA content for tropical and temperate New World pines}, volume={86}, ISSN={["1095-8290"]}, DOI={10.1006/anbo.2000.1272}, abstractNote={Abstract Temperate pine species have unusually large, complex genomes which make genomic analysis problematic; it has been suggested that tropical pines might have smaller genome sizes than temperate pines. Laser flow cytometry (LFC) was used to measure genome sizes of 11 species from Mexico, Guatemala and Nicaragua, spanning latitudes 14°–37° N. These values were compared with previously reported LFC estimates for 17 subtropical and temperate species. Genome sizes in this study were large, varying 1.6-fold from 19.94 to 31. 76 pg/C. Genome size variation paralleled taxonomic classification more closely than latitudinal origin. Genome sizes of subgenus Strobus(soft pines) were larger, ranging from 27.36 to 31.76 pg/C; those of subgenus Pinus(hard pines) were smaller, ranging from 19.94 to 24.91 pg/C. The exception was hard pine subsection Macrocarpae which had larger genome sizes ranging from 26.33 to 28.35. Intraspecific variation was substantial for tropical hard pines P. oocarpa andP. tecunumanii yet negligible for tropical hard pine P. patula.}, number={6}, journal={ANNALS OF BOTANY}, author={Hall, SE and Dvorak, WS and Johnston, JS and Price, HJ and Williams, CG}, year={2000}, month={Dec}, pages={1081–1086} }
 @inbook{dvorak_gutierrez_hodge_romero_stock_rivas_2000, title={Pinus caribaea var. hondurensis}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Gutierrez, E. A. and Hodge, G. R. and Romero, J. L. and Stock, J. and Rivas, O.}, year={2000}, pages={12} }
 @inbook{dvorak_gutierrez_osorio_merwe_kikuti_donahue_2000, title={Pinus chiapensis}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Gutierrez, E. A. and Osorio, L. F. and Merwe, L. and Kikuti, P. and Donahue, J. K.}, year={2000}, pages={34} }
 @inbook{dvorak_kietzka_donahue_hodge_stanger_2000, title={Pinus greggii}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Kietzka, J. E. and Donahue, J. K. and Hodge, G. R. and Stanger, T. K.}, year={2000}, pages={52} }
 @inbook{dvorak_kietzka_stanger_mapula_2000, title={Pinus herrerae}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Kietzka, J. E. and Stanger, T. K. and Mapula, M.}, year={2000}, pages={74} }
 @inbook{dvorak_jordan_rosa_hodge_2000, title={Pinus jaliscana}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Jordan, A. P. and Rosa, J. and Hodge, G. R.}, year={2000}, pages={86} }
 @inbook{dvorak_stanger_romero_2000, title={Pinus maximartinezii}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Stanger, T. K. and Romero, J. L.}, year={2000}, pages={96} }
 @inbook{dvorak_gutierrez_gapare_hodge_osorio_bester_kikuti_2000, title={Pinus maximinoi}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Gutierrez, E. A. and Gapare, W. J. and Hodge, G. R. and Osorio, L. F. and Bester, C. and Kikuti, P.}, year={2000}, pages={106} }
 @inbook{dvorak_gutierrez_osorio_hodge_brawner_2000, title={Pinus oocarpa}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Gutierrez, E. A. and Osorio, L. F. and Hodge, G. R. and Brawner, J. T.}, year={2000}, pages={128} }
 @inbook{dvorak_hodge_kietzka_malan_osorio_stanger_2000, title={Pinus patula}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Hodge, G. R. and Kietzka, J. E. and Malan, F. and Osorio, L. F. and Stanger, T. K.}, year={2000}, pages={148} }
 @inbook{dvorak_kikuti_fier_2000, title={Pinus pringlei}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Kikuti, P. and Fier, I.}, year={2000}, pages={174} }
 @inbook{dvorak_hodge_gutierrez_osorio_malan_stanger_2000, title={Pinus tecunumanii}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Hodge, G. R. and Gutierrez, E. A. and Osorio, L. F. and Malan, F. S. and Stanger, T. K.}, year={2000}, pages={188} }
 @inbook{dvorak_jordan_hodge_romero_woodbridge_2000, title={The evolutionary history of the Mesoamerican Oocarpae}, ISBN={0620264608}, booktitle={Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative}, publisher={Botha Hill, South Africa : Grow Graphics}, author={Dvorak, W. S. and Jordan, A. P. and Hodge, G. R. and Romero, J. L. and Woodbridge, W. C.}, year={2000}, pages={1} }
 @article{dvorak_hamrick_hodge_1999, title={Assessing the sampling efficiency of ex situ gene conservation efforts in natural pine populations in Central America}, volume={6}, number={1}, journal={Forest Genetics}, author={Dvorak, W. S. and Hamrick, J. L. and Hodge, G. R.}, year={1999}, pages={21} }
 @article{ledig_conkle_bermejo-velazquez_eguiluz-piedra_hodgskiss_johnson_dvorak_1999, title={Evidence for an extreme bottleneck in a rare Mexican pinyon: Genetic diversity, disequilibrium, and the mating system in Pinus maximartinezii}, volume={53}, ISSN={["1558-5646"]}, DOI={10.1111/j.1558-5646.1999.tb05335.x}, abstractNote={Maxipiñon (Pinus maximartinezii Rzedowski), which is confined to a single population of approximately 2000 to 2500 mature trees, covers about 400 ha in southern Zacatecas, Mexico. Genetic diversity measured by expected heterozygosity was 0.122, which is moderate for pines. However, percentage polymorphic loci was low, 30.3%. The fixation index (F) of 0.081 indicated only slight heterozygote deficiency. Mating system analysis indicated a significant but low level of selling; the multilocus outcrossing rate, tm, was 0.816. The mean of single locus estimates, ts, was smaller (0.761), perhaps suggesting mating among relatives, although the difference between tm and ts was not statistically significant.}, number={1}, journal={EVOLUTION}, author={Ledig, FT and Conkle, MT and Bermejo-Velazquez, B and Eguiluz-Piedra, T and Hodgskiss, PD and Johnson, DR and Dvorak, WS}, year={1999}, month={Feb}, pages={91–99} }
 @article{dvorak_uruena_moreno_goforth_1998, title={Provenance and family variation in Sterculia apetala in Colombia}, volume={111}, ISSN={["0378-1127"]}, DOI={10.1016/S0378-1127(98)00316-8}, abstractNote={Abstract Three provenances and 23 open-pollinated families of Sterculia apetala (Jacq.) Karst were established in a genetic field test in Zambrano, (Bolivar) northern Colombia (10° N lat.), where average annual rainfall is 920 mm. The provenances were Tiquisate, Guatemala, Cofradia, Honduras, and northern (Atlantico and Bolivar), Colombia. Growth and quality traits were measured over an 8-year period, and leaf initiation and wood specific gravity were assessed at age 10. The average height of S. apetala was 7.6 m at 8 years of age. The local Colombian provenance had 11% better survival, produced 28% more volume, and had better stem straightness than the best Central American provenance. Leaf initiation and leaf fall occurred in the introduced Central American sources earlier than in the local Colombian provenance and their timing appeared partly out of phase with the onset of the wet and dry seasons. Wood specific gravity averaged 0.208 at 10 years of age. The local Colombian source had significantly higher specific gravity than the introduced Central American sources, 0.216 vs. 0.204, respectively. There was a weak positive phenotypic correlation ( r =0.21) between height growth and wood specific gravity. Individual tree heritability for growth traits and quality traits ranged between 0.10 and 0.23. Individual tree heritability for leaf initiation was 0.05 and for specific gravity 0.44. Conservation and breeding efforts for S. apetala will continue to be minimal until new markets develop to utilize wood with low density.}, number={2-3}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Dvorak, WS and Uruena, H and Moreno, LA and Goforth, J}, year={1998}, month={Dec}, pages={127–135} }
 @article{moura_dvorak_hodge_1998, title={Provenance and family variation of Pinus oocarpa grown in the Brazilian cerrado}, volume={109}, ISSN={["1872-7042"]}, DOI={10.1016/S0378-1127(98)00265-5}, abstractNote={A Pinus oocarpa trial with six provenances and 46 open-pollinated families was planted on a deep Oxisol in 1983, at the EMBRAPA research station near Planaltina in the cerrado region of Brazil. This trial was part of the CAMCORE, North Carolina State University, international testing program. The provenances included in the test were: Camotan; San Luiz Jilotpeque; El Castaño; La Lagunilla (Guatemala) and San Marcos and Tablazon (Honduras). The trial was assessed at 13 years of age for a number of productivity and quality traits. El Castaño had better volume, and lower incidence of forks and multistems than the other provenances. Individual tree heritability for volume, stem form and branch diameter at 13 years of age was 0.29, 0.10, and 0.13, respectively. Selecting the best 25 trees in the best families would result in an estimated genetic gain of more than 30% in the next generation. Comparison of results from this test with other CAMCORE P. oocarpa trials in Colombia and Venezuela suggest that both provenance×site and family×site interactions can be of biological importance.}, number={1-3}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Moura, VPG and Dvorak, WS and Hodge, GR}, year={1998}, month={Sep}, pages={315–322} }
 @article{dvorak_rosa_mapula_reyes_1998, title={The ecology and conservation of Pinus jaliscana}, number={26}, journal={Forest Genetic Resources}, author={Dvorak, W. S. and Rosa, J. A. and Mapula, M. and Reyes, V. J.}, year={1998}, pages={13} }
 @article{saborio_dvorak_donahue_thorpe_1997, title={In vitro regeneration of plantlets from mature embryos of pinus ayacahuite}, volume={17}, DOI={10.1093/treephys/17.12.787}, abstractNote={A plantlet regeneration protocol was developed for Pinus ayacahuite var. ayacahuite (Ehrenb.). Embryos from mature seeds from ten provenances were cultured in a 16-h photoperiod for 3 days on a medium containing 30 mM sucrose and 0.7% agar. Cotyledons from these embryos were subcultured onto MCM medium (Bornman 1983) supplemented with 50 micro M N(6)-benzyladenine and 90 mM sucrose for 2 weeks. Bud development and shoot elongation were maximized by subculturing the explants on half strength AE medium (von Arnold and Ericksson 1981), supplemented with 60 mM sucrose and 0.05% activated charcoal every 30 days. Seed source had a significant effect on the responses of the embryos to the bud induction protocol. For the provenance with the best response to bud induction, about 79% of the cultured cotyledons formed buds, and each cotyledon formed a mean of 9.1 buds, so that about 70 shoots could be induced from each seed. The best rooting response (40% rooting) was obtained by treating the shoots for 8 h with 100 micro M naphthalene acetic acid.}, number={12}, journal={Tree Physiology}, author={Saborio, F. and Dvorak, William S. and Donahue, J. K. and Thorpe, T. A.}, year={1997}, pages={787–796} }
 @article{dvorak_donahue_hodge_1996, title={Fifteen years of ex situ gene conservation of Mexican and Central American forest species by the CAMCORE cooperative}, number={24}, journal={Forest Genetic Resources}, author={Dvorak, W. S. and Donahue, J. K. and Hodge, G. R.}, year={1996}, pages={15} }
 @article{dvorak_donahue_vasquez_1996, title={Provenance and progeny results for the tropical white pine, Pinus chiapensis, at five and eight years of age}, volume={12}, number={2}, journal={New Forests}, author={Dvorak, W. S. and Donahue, J. K. and Vasquez, J. A.}, year={1996}, pages={125} }
 @article{dvorak_kietzka_donahue_1996, title={Three-year survival and growth of provenances of Pinus greggii in the tropics and subtropics}, volume={83}, ISSN={["0378-1127"]}, DOI={10.1016/0378-1127(95)03673-3}, abstractNote={Eleven provenance/progeny tests of Pinus greggii Engelm. were assessed for survival and height at 3 years of age in Brazil, Colombia and South Africa. Trees of P. greggii from sources in northern Mexico (≈ 25°N latitude) were less than half as tall as trees from provenances in central Mexico (≈ 21°N latitude) when established in warm climates of Brazil and Colombia, (4.2 m vs. 1.6 m, respectively). The differences in height growth diminished between southern and northern sources in more temperate climates in South Africa (2.9 m vs. 2.1 m, respectively). External morphological differences in foliage were also pronounced between trees of the two regions when grown as an exotic. Trees from northern sources had shorter, stiffer, needles of darker green color than those from southern provenances. The most promising of the southern provenances across all sites were El Madroño (Queretaro) and Laguna Seca (Hidalgo). La Tapona (Nuevo Leon) and Los Lirios (Coahuila) performed well among the northern sources. Pinus greggii should be tested where low rainfall and cold are considered limiting factors for good growth of P. patula.}, number={1-2}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Dvorak, WS and Kietzka, JE and Donahue, JK}, year={1996}, month={Jun}, pages={123–131} }
 @article{dvorak_donahue_vasquez_1995, title={Early performance of CAMCORE introductions of Pinus patula in Brazil, Colombia and South Africa}, DOI={10.1080/00382167.1995.9629875}, abstractNote={SYNOPSIS Seeds were collected from 13 provenances and 282 mother trees of Pinus patula Schiede & Deppe across a 900 km transect from Tamaulipas to Oaxaca, Mexico by the CAMCORE Cooperative, North Carolina State University, USA. Thirty-three provenance/progeny tests were established in Brazil, Colombia, and South Africa and assessed for height and diameter (DBH) at three years of age. Sources from southern Oaxaca (Cuajimoloyas, Manzanal, and Tlacuache) showed great susceptibility to cold at Jessievale and Commonage, South Africa (26% survival) versus the other P. patula sources (70% survival). Average height growth at three years of age exceeded 5 m in tests at Los Guadales, Colombia, and Maxwell, South Africa. The best provenances for height growth and volume in both Brazil and South Africa were those from the central part of the P. patula range: Potrero de Monroy (Veracruz), Zacualtipan, (Hidalgo) and Pinal de Amoles (Queretaro). In the Andean mountains of Colombia, the southern Oaxacan sources of P. patula performed as well as the best sources from central Mexico. Some CAMCORE open-pollinated families performed as well as or better in height growth than advanced generation control lots of P. patula, P. taeda or P. elliottii in 29 of 33 tests.}, number={174}, journal={Southern African Forestry Journal}, author={Dvorak, W. S. and Donahue, J. K. and Vasquez, J. A.}, year={1995}, pages={23} }
 @article{dvorak_ross_1994, title={3-YEAR GROWTH AND STABILITY OF HONDURAN PROVENANCES AND FAMILIES OF PINUS-TECUNUMANII}, volume={63}, ISSN={["0378-1127"]}, DOI={10.1016/0378-1127(94)90243-7}, abstractNote={Two orthogonal sets of five trials of P. tecunumanii were established by the CAMCORE Cooperative at several locations in Brazil, Guatemala, South Africa and Venezuela. Sets A and B included 46 and 35 half-sib families, respectively, from the provenances of Jocón, San Francisco, San Esteban and Villa Santa, Honduras. Results from assessment of 3-year height indicated that trees from San Francisco, San Esteban and Villa Santa were equally productive across all sites and should be further tested on a modest scale. Provenance x site interaction in both sets was contributed primarily by the poorest source, Jocón. Of the families tested, 17% were found to have b coefficients less than 0.85 or more than 1.15 or R2 values less than 0.90 and were classified as interactive across environments. The relatively few families causing the significant interaction and the positive significant Spearman rank correlations (r) between most sites of close geograpjic proximity suggested that genotype x site interactions were not serious. However, Spearman rank correlations (r) between sites separated by thousands of kilometers were often less than 0.30 and not significant. When selections from one location are moved large geographic distances, they should first be tested in trials in the new environment before being included in the breeding population.}, number={1}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={DVORAK, WS and ROSS, KD}, year={1994}, month={Jan}, pages={1–11} }
 @article{dvorak_lambeth_li_1993, title={Genetic and site effects on stem breakage in Pinus tecunumanii}, volume={7}, DOI={10.1007/bf00127388}, number={3}, journal={New Forests}, author={Dvorak, W. S. and Lambeth, C. C. and Li, B. L.}, year={1993}, pages={237} }
 @article{dvorak_kellison_1991, title={Annotated bibliography on the wood properties of Pinus tecunumanii}, number={9}, journal={CAMCORE Bulletin on Tropical Forestry}, publisher={Central America & Mexico Coniferous Resources Cooperative (CAMCORE)}, author={Dvorak, W. S. and Kellison, R. C.}, year={1991}, pages={16} }
 @article{dvorak_1990, title={CAMCORE - INDUSTRY AND GOVERNMENTS EFFORTS TO CONSERVE THREATENED FOREST SPECIES IN GUATEMALA, HONDURAS AND MEXICO}, volume={35}, ISSN={["0378-1127"]}, DOI={10.1016/0378-1127(90)90238-7}, abstractNote={Abstract In 1980, the Central America and Mexico Coniferous Resources Cooperative (CAMCORE) was organized by forest industry, government agencies, and the College of Forest Resources, North Carolina State University, to preserve and test threatened forest species and populations in Middle America. The cooperative has now grown to include 16 organizations in nine countries. Explorations and subsequent seed collections in Guatemala, Honduras and Mexico have resulted in the successful ex-situ gene conservation of 5203 trees, representing 21 species and 187 different provenances of conifers and hardwoods. Genetic material from the Central American and Mexican seed collections have been established in 500 ha of gene-conservation banks and genetic tests on lands belonging to members of the cooperative in Brazil, Colombia, Costa Rica, Guatemala, Honduras, Mexico, South Africa, the United States, and Venezuela. Pedigree information on mother-tree collections and subsequent field plantings is on computer database at North Carolina State University. Early results from CAMCORE genetic tests indicate that height gains of approximately 20% are possible in the tropics by simply using alternative species and more-productive seed sources. Cooperative-wide tree improvement programs are now being planned for Pinus caribaea and P. tecunumanii .}, number={1-2}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={DVORAK, WS}, year={1990}, month={Jun}, pages={151–157} }
 @article{dvorak_raymond_1990, title={The taxonomic status of closely related closed cone pines in Mexico and Central America}, volume={4}, DOI={10.1007/bf00119208}, number={4}, journal={New Forests}, author={Dvorak, W. S. and Raymond, R. H.}, year={1990}, pages={291} }
 @article{dvorak_donahue_1988, title={Pinus maximinoi seed collections in Mexico and Central America}, number={4}, journal={CAMCORE Bulletin on Tropical Forestry}, publisher={Central America and Mexico Coniferous Resources Cooperative, North Carolina State University}, author={Dvorak, W. S. and Donahue, J. K.}, year={1988}, pages={47} }