A Variety or a Separate Species?

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582.632.1:575.858

DOI:

10.37482/0536-1036-2020-1-26-48

Abstract

Curly (Karelian) birch is a unique and highly valuable representative of woody flora, whose natural growth has been preserved only in the north-west of continental Europe. The article recapitulates the development of views on the taxonomic status and systematic position of the birch. We have analyzed the numerous facts and observations, which, from our perspective, bear record to correspondence of curly birch to the species taxonomic rank. It was done based on our own and published data, and in accordance with generally accepted criteria of the species (morphological, biochemical, genetic, reproductive, geographical, and ecological). The issues of separateness and relatedness of the birch to other representatives of the genus Betula L. are considered. It is emphasized that the recognition of curly birch as a separate biological species is important not only for scientific reasons, but also has great environmental significance since international and national nature protection documents, regulations and laws are focused on animals and plants with a species status.

Authors

L. V. Vetchinnikova¹, Doctor of Biology, Assoc. Prof., Chief Research Scientist; ResearcherID: J-5665–2018, ОRCID: 0000-0003-2091-905X
A. F. Titov^2,3, Corresp. Member of RAS, Doctor of Biology, Prof., Head of Laboratory, Chief Research Scientist; ResearcherID: A-6705–2014, ORCID: 0000-0001-6880-2411

Affiliation

¹Forest Research Institute of Karelian Research Centre, Russian Academy of Sciences, ul. Pushkinskaya, 11, Petrozavodsk, Republic of Karelia, 185910, Russian Federation; е-mail: vetchin@krc.karelia.ru
²Institute of Biology of Karelian Research Centre, Russian Academy of Sciences, ul. Pushkinskaya, 11, Petrozavodsk, Republic of Karelia, 185910, Russian Federation
³Department of Multidisciplinary Scientific Research of Karelian Research Centre, Russian Academy of Sciences, ul. Pushkinskaya, 11, Petrozavodsk, Republic of Karelia, 185910, Russian Federation; е-mail: titov@krc.karelia.ru

Keywords

curly birch Betula pendula Roth var. carelica (Mercklin) Hämet-Ahti, taxonomic status, species criteria, Republic of Karelia

Funding

The study was carried out within the framework of the state assignment of the Karelian Research Centre of the Russian Academy of Sciences (Forest Research Institute, Institute of Biology, and Department of Multidisciplinary Scientific Research) and covered by the federal budget.

For citation

Vetchinnikova L.V., Titov A.F. Curly Birch: A Variety or a Separate Species? Lesnoy Zhurnal [Russian Forestry Journal], 2020, no. 1, pp. 26–48. DOI: 10.37482/0536-1036-2020-1-26-48

References

1. Alekseyeva A.I. Diagnostic Signs of Curly Birch Wood. Lesnoy Zhurnal [Russian Forestry Journal], 1962, no. 3, pp. 33–37. URL: http://lesnoizhurnal.ru/ apxiv / 1962. pdf
2. Altukhov Yu. P. Species and Speciation. Sorosovskiy obrazovatel’nyy zhurnal [Soros Educational Journal], 1997, no. 4, pp. 2–10.
3. Bagayev S. N. Karelian and Burr-Root Birch in the Forests of Kostroma Region. Lesnoye khozyaystvo, 1963, no. 6, pp. 20–22.
4. Baranov O.Yu. The Population and Genetic Structure of Representatives of the Genus Betula L. in Belarus, and Its Application in Forest Selection: Cand. Agric. Sci. Diss.Abs. Gomel, 2003. 24 p.
5. Baranov O.Yu., Balyutskas V. M. Using Molecular Genetic Markers for Analysis of Aspen and Birch Ploidy. Issues of Forest Science and Forestry: Collection of Academic Papers. Gomel, IL NaN of Belarus Publ., 2009, iss. 69, pp. 129-135.
6. Baranov O.Yu., Markovskaya Yu.A. Features of Genetic Structure of Curly Birch by Gpi-2 Gene. Issues of Forest Science and Forestry: Collection of Academic Papers. Gomel, IL NaN of Belarus Publ., 2003, iss. 50, pp. 181–185.
7. Baranov O.Yu., Nikolayeva N. N., Mashkina O. S., Balyutskas V.M. Phylogenetic Analysis of Curly Birch Based on Alcohol Dehydrogenase Gene Sequencing Data. Structural and Functional Abnormalities of Growth and Development of Plants under the Influence of Environmental Factors: Proceedings of the International Conference. Petrozavodsk, KarRC RAS Publ., 2011, pp. 24–29.
8. Butorina A.K. Cytogenetics of Economically Valuable Forms of Curly Birch. Genetika [Soviet Genetics], 1985, vol. 21, no. 7, pp. 1192–1198.
9. Butorina A. K. On the Nature of Curly Birch Wood Veins. Genetic and Ecological Principles of Forest Productivisation: Collection of Academic Papers. Voronezh, NIILGiS Publ., 1993, pp. 40–47.
10. Vetchinnikova L.V. Birch: Variability Problems (Morpho-Physiological and Biochemical Aspects). Moscow, Nauka Publ., 2004. 183 p.
11. Vetchinnikova L.V. Karelian Birch and Other Rare Representatives of the Genus Betula L. Moscow, Nauka Publ., 2005. 269 p.
12. Vetchinnikova L.V., Titov A. F. The Origin of the Karelian Birch: An Ecogenetic Hypothesis. Russian Journal of Genetics: Applied Research, 2017, vol. 7, iss. 6, pp. 665–677. DOI: 10.1134 / S2079059717060144
13. Vetchinnikova L.V., Titov A. F. Karelian Birch in Sanctuaries in the Republic of Karelia: History, Current State, Problems. Botanicheskii Zhurnal [Botanical journal], 2018, vol. 103, no. 2, pp. 256–265. DOI: 10.1134 / S0006813618020096
14. Vetchinnikova L., Titov A., Kuznetsova T. Curly Birch: Biological Characteristics, Resource Dynamics, and Reproduction. Petrozavodsk, KarRC RAS Publ., 2013. 312 p.
15. Galibina N.A., Moshkina E.V., Nikerova K.M., Moshchenskaya Yu.L., Znamenskii S.R. Peroxydase Activity Indicates Veining of Curly Birch. Lesovedenie [Russian Journal of Forest Science], 2016, no 4, pp. 294–304.
16. Ganyushkina L. G. Description of Some Physiological Parameters of Curly Birch. Ways of Adaptation of Organisms in the North. Petrozavodsk, PetrGU Publ., 1978, pp. 28–29.
17. Evdokimov A. P. Biology and Crop of Curly Birch. Leningrad, LSU Publ., 1989. 228 p.
18. Ermakov V.I. Mechanisms of Birch Adaptation to the North Conditions. Leningrad, Nauka Publ., 1986. 144 p.
19. Kachalov A.A. Trees and Shrubs. Moscow, Lesnaya promyshlennost’ Publ., 1970. 408 p.
20. Kosichenko N.E., Shchetinkin S.V. Structural Aspects of Differentiation and Diagnosis of Wood Veins in Curly Birch. Modern Aspects of Wood Science: Abstracts of the All-Union Conference (September 22–24, 1987). Krasnoyarsk, ILID Publ., 1987, pp. 27–29.
21. Kravets E.A. Cytomixis and Its Role in the Regulation of Plant Fertility. Ontogenez [Russian Journal of Developmental Biology], 2013, vol. 44, no. 3, pp. 147–165. DOI: 10.7868 / S0475145013030038
22. Red Book of the Republic of Karelia. Petrozavodsk, Kareliya Publ., 2007. 368 p.
23. Lyubavskaya A.Ya. Selection and Introduction of Karelian Birch: Dr. Agric. Sci. Diss.Abs. Moscow, 1969. 48 p.
24. Lyubavskaya A.Ya. Karelian Birch and Its Place in the System of the Genus Betula. Regularities of Intraspecific Variability of Hardwood Species: Collection of Academic Papers. Sverdlovsk, UNTs AN SSSR Publ., 1975, pp. 111–114.
25. Lyubavskaya A.Ya. Karelian Birch. Moscow, Lesnaya promyshlennost’ Publ., 1978. 158 p.
26. Mayr E. Populations, Species, and Evolution. Moscow, Mir Publ., 1974. 460 p.
27. Maslov A.A., Baranov O.Yu., Sirin A.A. A Molecular Genetics Study of Silver and Downy Birches in Peatland and Paludified Forest Types in the Middle of the East European Plain. Lesovedenie [Russian Journal of Forest Science], 2019, no. 3, pp. 177–187. DOI: 10.1134 / S0024114819020062
28. Matveeva T.V., Mashkina O.S., Isakov Y. N., Lutova L.A. Molecular Passportization of Clones of Karelian Birch Using PCR with Semi-Specific Primers. Ekologicheskaya genetika [Ecological genetics], 2008, vol. 6, no. 3, pp. 18–23.
29. Mashkina O.S., Butorina A. K., Tabatskaya T.M. Karelian Birch (Betula pendula Roth. var. carelica Merkl.) as a Model for Studying Genetic and Epigenetic Variation Related to the Formation of Patterned Wood. Genetika [Russian Journal of Genetics], 2011, vol. 47, no. 8, pp. 1073–1080. DOI: 10.1134 / S1022795411080126
30. Merklin K. Anatomy of Bark and Stem Wood of Different Forest Trees and Shrubs in Russia. Saint Petersburg, Tipografiya Yakova Treya, 1857. 101 p.
31. Nikerova K. M., Galibina N.A.,  Moshchenskaya Yu. L., Novitskaya L.L., Podgornaya M. N., Sofronova I.N. Contribution of Catalase and Peroxidase to Xylogenesis of Karelian Birch. Lesovedenie [Russian Journal of Forest Science], 2019, no. 2, pp. 115–127. DOI: 10.1134 / S0024114819020086
32. Nikolaevskaya T.S., Vetchinnikova L.V., Lebedeva O.N., Kuznetsova T.Yu. Morphophysiological Characteristics of Pollen of Various Birch Species in Eastern Fennoscandia. Trudy Karel’skogo nauchnogo tsentra RAN. Seriya: Biogeografiya [Transactions of the Karelian Research Centre of RAS. Series: Biogeography], 2008, iss. 14, pp. 84–91.
33. Nikolaevskaya T. S., Vetchinnikova L.V., Titov A.F., Lebedeva O.N. Study of Pollen in Native and Introduced Betula Species in Karelia. Trudy Karel’skogo nauchnogo tsentra RAN. Seriya: Biogeografiya [Transactions of the Karelian Research Centre of RAS. Series: Biogeography], 2009, iss. 4, pp. 90–95.
34. Pobirushko V.F. Distribution and Variability of Karelian Birch in Belarus. Botany: Collection of Academic Papers. Minsk, Navuka i tekhnika Publ., 1992, iss. 31, pp. 31–39.
35. Pogiba S.P. Polymorphism of Vital Forms of Karelian Birch in the Context of the Theory of Somatic Evolution. Structural and Functional Abnormalities of Growth and Development of Plants under the Influence of Environmental Factors. Proceedings of the International Conference. Petrozavodsk, KarRC RAS Publ., 2011, pp. 245–249.
36. Red’ko G.I. Forest Expert F.G. Fokel’ in Russia. Lesnoy Zhurnal [Russian Forestry Journal], 1990, no. 5, p. 129–131. URL: http://lesnoizhurnal.ru/apxiv/1990/1990 % 20№%205. pdf
37. Sidorchuk Yu.V., Deineko E.V., Shumny V.K. Peculiarities of the Cytomixis in the Pollen Mother Cells of Transgenic Tobacco Plants (Nicotiana tabacum L.) with Mutant Phenotype. Tsitologiya [Cell Tissue and Biology], 2007, vol. 49, no. 10, pp. 870–875.
38. Sokolov N. O. Karelian Birch. Trudy LTA, 1938, iss. 53, pp. 87–96.
39. Sokolov N. O. Karelian Birch. Petrozavodsk, Gosudarstvennoye izdatelstvo Karelo-Finskoy SSR, 1950. 116 p.
40. Sokolov N. O. Tasks of the Further Study of Karelian Birch. Izvestiya Karel’skogo i Kol’skogo filialov АN SSSR, 1958, no. 3, pp. 96–102.
41. Sokolov N.O. Selection of Karelian Birch in Forests and Plantations of the North-West. Regularities of Intraspecific Variability  of Hardwood Species: Collection of Academic Papers. Sverdlovsk, UNTs AN SSSR Publ., 1975, pp. 111–114.
42. Solov’yeva N.M. To the Caryological Study of Birches. Byulleten` Glavnogo botanicheskogo sada [Bulletin of the Central Botanical Garden], 1977, no. 106, pp. 100–103.
43. Fedulova T. P., Isakov Y.N., Korchagin O. M., Isakov I. Y., Kondratyeva A.M., Rzhevskiy S. G. Molecular-Genetic Differentiation of Genotypes of Birch Based on SSR-Markers Polymorphism. Lesotekhnicheskij zhurnal [Forestry Engineering Journal], 2017, vol. 7, no. 4, pp. 6–16. DOI: 10.12737 / article_5a3cef5a94cab2.12952001
44. Tsvelev N.N. On the Genera Betula L. and Alnus Mill (Betulaceae) in Eastern Europe. Novosti sistematiki vysshikh rasteniy [Novitates Systematicae Plantarum Vascularium], 2002, iss. 34, pp. 47–73.
45. Shulyakovskaya T. A, Vetchinkikova L. V, Repin A.V., Schrеders S.M. Dynamics of Amino Acid Content in Buds and Leaves of Betula pubescens and B. pendula (Betulaceae) during the Vegetation Period. Rastitelnye Resursy, 2007, vol. 43, no. 4, pp. 87–94.
46. Shchetinkin S.V. Histogenesis of Veined Wood in Betula pendula Roth var. carelica Mercl. and Betula pendula Roth: Cand. Agric. Sci. Diss.Abs. Voronezh, 1988. 24 p.
47. Eglite G.K., Oshkaya V. P. Free Amino Acids in Karelian Birch. Izvechtiya AN Latviyskoy SSR, 1973, no. 1, pp. 15–20.
48. Yakovlev F.S. Anatomical Structure of Karelian Birch Trunk. Izvestiya Karelo-Finskoy nauchnoissledovatel’skoy bazy AN SSSR, 1949, no. 1, pp. 3–19.
49. Ahokas H. Cytokinins in the Spring Sap of Curly Birch (Betula pendula f. carelica) and the Non-Curly Form. Journal of Plant Physiology, 1985, vol. 118, iss. 1, pp. 33-39. DOI: 10.1016 / S0176–1617 (85) 80162-0
50. Anamthawat-Jónsson K., Thór Thórsson A. Natural Hybridization in Birch: Triploid Hybrids between Betula nana and B. pubescens. Plant Cell, Tissue and Organ Culture, 2003, vol. 75, iss. 2, pp. 99-107. DOI: 10.1023 / A:1025063123552
51. Bina H., Yousefzadeh H., Esmaeilpour M., Esmaeilzadeh O. Molecular Identification of the Genus Betula Based on ITS Sequence Data and Its Secondary Structure in Iran. Iranian Journal of Rangelands and Forests Plant Breeding and Genetic Research, 2014, vol. 22, no. 2 (44), pp. 168–180.
52. Consensus Document on the Biology of European White Birch (Betula pendula Roth). Series on Harmonization of Regulatory Oversight in Biotechnology, No. 28. Paris, OECD, 2003. 45 p.
53. Convention on Biological Diversity. Rio de Janeiro, United Nations, 1992. 28 p. Available at: https://www.cbd.int / convention / text / (accessed 22.04.19).
54. Dąbrowska G., Dzialuk A., Burnicka O., Ejankowski W., Gugnacka-Fiedor W., Goc A. Genetic Diversity of Postglacial Relict Shrub Betula nana Revealed by RAPD Analysis. Dendrobiology, 2006, vol. 55, pp. 19-23. DOI: 10.13140 / RG. 2.1.2160.8488
55. Etholén K., Huuri L. Visakoivua käsittelevä kirjallisuus [Bibliography on Curly Birch, Betula pendula var. carelica (Mercklin)]. Folia Forestalia, 1982, vol. 502. 24 p.
56. Hagman M. On Self- and Cross-Incompatibility Shown by Betula verrucosa Ehrh. and Betula pubescens Ehrh. Communicationes Instituti Forestalis Fenniae, 1971, vol. 73 (6), pp. 1–125.
57. Hämet-Ahti L., Palmén A., Alanko P., Tigerstedt P.V. A. Suomen puu- ja pensaskasvio [Woody Flora of Finland]. Helsinki, Dendrologian Seura, 1989. 290 p.
58. Hämet-Ahti L., Palmén A., Alanko P., Tigerstedt P.V. A. Suomen puu- ja pensaskasvio [Woody Flora of Finland]. Helsinki, Dendrologian Seura, 1992. 373 p.
59. Hejtmánek G. Betula pendula var. carelica Sokolov v Československu. Preslia, 1957, vol. 29, pp. 264–268.
60. Hintikka T. J. Die “Wisa” – Krankheit der Birken in Finnland. Zeitschrift fur Pflanzenkrankheiten und Gallenkunde, 1922, B. 32, Nr. 5/6, S. 193–210.
61. Hodnebrog T. Valbjørk: produksjon på utvalgte kloner. Ås, Forskningsparken, 1996. 3 p.
62. Howland D. E., Oliver R. P., Davy A. J. Morphological and Molecular Variation in Natural Populations of Betula. New phytologist, 1995, vol. 130, iss. 1, pp. 117–124. DOI: 10.1111 / j. 1469-8137.1995. tb01821. x
63. Hu Y.-N., Zhao L., Buggs R. J. A, Zhang X.-M., Li J., Wang N. Population Structure of Betula albosinensis and Betula platyphylla: Evidence for Hybridization and a Cryptic Lineage. Annals of Botany, 2019, vol. 123, iss. 7, pp. 1179–1189. DOI: 10.1093 / aob / mcz024
64. Hynynen J., Niemistö P., Viherä-Aarnio A., Brunner A., Hein S., Velling P. Silviculture of Birch (Betula pendula Roth and Betula pubescens Ehrh.) in Northern Europe. Forestry, 2010, vol. 83, iss. 1, pp. 103–119. DOI: 10.1093 / forestry / cpp035
65. Jadwiszczak K.A. What Can Molecular Markers Tell Us about the Glacial and Postglacial Histories of European Birches? Silva Fennica, 2012, vol. 46, no. 5, pp. 733–745. DOI: 10.14214 / sf. 923
66. Järvinen P., Palmé A., Morales L.O., Lännenpää M., Keinänen M., Sopanen T., Lascoux M. Phylogenetic Relationships of Betula species (Betulaceae) Based on Nuclear ADH and Chloroplast matK Sequences. American Journal of Botany, 2004, vol. 91, iss. 11, pp. 1834–1845. DOI: 10.3732 / ajb. 91.11.1834
67. Johnsson H. Avkommor av masurbjork [Progeny of Curly Birch]. Svenska SkogavForen. Tidskr., 1951, Bd. 49, Nr. 1, S. 34–45.
68. Jonsell B. Flora Nordica: Lycopodiaceae – Polygonaceae (Vol. 1). Stockholm, The Bergius Foundation, 2000. 344 p.
69. Karlík P. Taxonomická problematika bříz Betula L. v České Republice se zvláštním zřetelem na drobné taxony z okruhu břízy pýřité Betula pubescens agg. [Taxonomical Problematic of the Genus Betula L. in the Czech Republic with Special Respect on Taxons from Group Betula pubescens agg.]. Bříza – strom roku 2010: sborník z konference. Kostelec nad Černými lesy, 23 září 2010. Praze, Česká zemědělská univerzita, 2010, pp. 61–65.
70. Kosonen M. Visakoivu – Curly Birch. Finland, Metsäkustannus Oy, 2004. 197 p.
71. Lascoux M., Palmé A.E., Cheddadi R., Latta R.G. Impact of Ice Ages on the Genetic Structure of Trees and Shrubs. Philosophical Transactions of the Royal Society B: Biological Sciences, 2004, vol. 359, iss. 1442, pp. 197–207. DOI: 10.1098 / RSTB. 2003.1390
72. Li J., Shoup S., Chen Z. Phylogenetics of Betula (Betulaceae) Inferred from Sequences of Nuclear Ribosomal DNA. Rhodora, 2005, vol. 107, no. 929, pp. 69–86. DOI: 10.3119 / 04-14.1
73. Lindquist B. Forstgenetik in der schwedischen Waldbaupraxis. Radebeul und Berlin, Neumann Verlag, 1954. 156 S.
74. Maliouchenko O., Palmé A. E., Buonamici A., Vendramin G. G., Lascoux M. Comparative Phylogeography and Population Structure of European Betula Species, with Particular Focus on B. pendula and B. pubescens. Journal of Biogeography, 2007, vol. 34, iss. 9, pp. 1601–1610. DOI: 10.1111 / j. 1365-2699.2007.01729. x
75. Nagamitsu T., Kawahara T., Kanazashi A. Endemic Dwarf Birch Betula apoiensis (Betulaceae) is a Hybrid that Originated from Betula ermanii and Betula ovalifolia. Plant Species Biology, 2006, vol. 21, iss. 1, pp. 19–29. DOI: 10.1111 / j. 1442-1984.2006.00147. x
76. Nowakowska Ju.A. Application of DNA Markers against Illegal Logging as a New Tool for the Forest Guard Service. Folia Forestalia Polonica, Series A, 2011, vol. 53, no. 2, pp. 142–149.
77. Palme A.E., Su Q., Palsson S., Lascoux M. Extensive Sharing of Chloroplast Haplotypes among European Birches Indicates Hybridization among Betula pendula, B. pubescens and B. nana. Molecular Ecology, 2004, vol. 13, iss. 1, pp. 167-178. DOI: 10.1046 / j.1365-294X. 2003.02034. x
78. Palmé A.E., Su Q., Rautenberg A., Manni F., Lascoux M. Postglacial Recolonization and cpDNA Variation of Silver Birch, Betula pendula. Molecular Ecology, 2003, vol. 12, iss. 1, pp. 201–212. DOI: 10.1046 / j. 1365-294X. 2003.01724. x
79. Pätiälä R.V. Pirun puristama visakoivu. Suomen Luonto, 1980, vol. 39, no. 1, pp. 3–5.
80. Pekkinen M., Varvio S., Kulju K.K. M., Kärkkäinen H., Smolander S., Viherä Aarnio A., Koski V., Sillanpää M. J. Linkage Map of Birch, Betula pendula Roth, Based on Microsatellites and Amplified Fragment Length Polymorphisms. Genome, 2005, vol. 48(4), pp. 619–625. DOI: 10.1139 / g05–031
81. Raulo J., Sirén G. Neljän visakoivikon päätehakkuun tuotos ja tuotto [Yield in Volume and Money of Final Cutting in Four Curly Birch Stands]. Silva Fennica, 1978, vol. 12, no. 4, pp. 245–252. DOI: 10.14214 / sf. a14862
82. Regel E. Bemer Kungen über die Gattungen Betula und Alnus nebst Beschreibung einiger neuer arten. Bull.Soc. Nature. Mosguae, 1865, vol. 38, no. 4, pp. 388–434.
83. Ruden T. Om valbjørk og endel andre unormale veddannelser hos bjørk [Summary: On Speckled Birch (Mazer-Birch) and Some Other Forms of Curled Birch]. Meddelelser fra Det Norske Skogforsøksvesen, 1954, vol. 43, no. 12, pp. 454–505.
84. Saarnio R. Viljeltyjen visakoivikoiden laatu ja kehitys Etelä-Suomessa [The Quality and Development of Cultivated Curly-Birch (Betula verrucosa f. carelica Sok.) Stands in Southern Finland]. Folia Forestalia, 1976, no. 263, pp. 1–28.
85. Saarnio R. Visakoivu – vuoden puu. Dendrologian seuran tiedotuksia, 1980, vol. 11, no. 1, pp. 4–14.
86. Salojärvi J., Smolander O.-P., Nieminen K., Rajaraman S., Safronov O., Safdari P. et al. Genome Sequencing and Population Genomic Analyses Provide Insights into the Adaptive Landscape of Silver Birch. Nature Genetics, 2017, vol. 49, pp. 904–912. DOI: 10.1038 / ng. 3862
87. Sarvas R. Visakoivikon perustaminen ja hoito. Metsätal Aikakauslehti, 1966, vol. 83, no. 8, pp. 331–333.
88. Schenk M. F., Thienpont C.-N., Koopman W. J. M., Gilissen L.J. W. J., Smulders M.J.M. Phylogenetic Relationships in Betula (Betulaceae) Based on AFLP Markers. Tree Genetics & Genomes, 2008, vol. 4, pp. 911–924. DOI: 10.1007 / s11295-008-0162-0
89. Scholz E. Die rationelle Bewirtschaftung der Birke. Sozialistische Forstwirtschaft, 1963, Bd. 13, Nr. 12, S. 362–367.
90. Svoboda P. Lesní dřeviny a jejich porosity. Část 3. Praha, Státní zemědĕlské nakladatelství, 1957. 457 s.
91. Thomson A.M., Dick C.W., Pascoini A.L., Dayanandan S. Despite Introgressive Hybridization, North American Birches (Betula spp.) Maintain Strong Differentiation at Nuclear Microsatellite Loci. Tree Genetics & Genomes, 2015, vol. 11, no. 5, art. 101. 12 p. DOI: 10.1007 / s11295-015-0922-6
92. Vetchinnikova L.V., Titov A. F. The Origin of the Karelian Birch: An Ecogenetic Hypothesis. Russian Journal of Genetics: Applied Research, 2017, vol. 7, iss. 6, pp. 665–677. DOI: 10.1134 / S2079059717060144
93. Vetchinnikova L., Titov A. The Mysteries of the Origin of the Curly Birch. Thünen Report 62: Proceedings of the German Russian Conference on Forest Genetics,  Ahrensburg, November 21–23, 2017. Braunschweig, Germany, 2018, pp. 55–60. DOI: 10.3220 / REP1539855736000
94. Wang N., McAllister H. A., Bartlett P. R., Buggs R.J. A. Molecular Phylogeny and Genome Size Evolution of the Genus Betula (Betulaceae). Annals of Botany, 2016, vol. 117, iss. 6, pp. 1023–1035. DOI: 10.1093 / aob / mcw048
95. Wang N., Thomson M., Bodles W.J. A., Crawford R. M. M., Hunt H.V., Featherstone A. W., Pellicer J., Buggs R.J. A. Genome Sequence of Dwarf Birch (Betula nana) and Cross-Species RAD Markers. Molecular Ecology, 2013, vol. 22, iss. 11, pp. 3098–3111. DOI: 10.1111 / mec. 12131
96. Watterson G.A., Guess H.A. Is the Most Frequent Allele the Oldest? Theoretical Population Biology, 1977, vol. 11, iss. 2, pp. 141–160. DOI: 10.1016 / 0040-5809 (77) 90023-5
 

Received on April 22, 2019