Pinus heldreichii

H. Christ 1863

Common names

Munika, cherna mura [=Black pine: Bulgarian, Serbian], whitebark pine, Heldreich pine, Bosnian pine [English], Panzerkiefer [German], pin d'ecorce blanche [French], il pino loricato [Italian] (Janković 1986), robolo [Greek]; var. leucodermis called palebark pine (Biondi 1992) or Bosnian pine (Farjon 1984).

Taxonomic notes

One variety, leucodermis (Antoine) Markgraf ex Fitschen (syn: P. leucodermis Antoine; P. laricio var. leucodermis (Ant.) Christ) (Farjon 1984, Silba 1986). This variety is often treated as a distinct species, particularly by the Italians, who are rightly proud of it. Of the 16 species with which it shares subsection Pinus, it most nearly resembles P. nigra (Farjon 1984).

Description

Trees to 20(-35) m tall, but often shrubby; dbh to more than 2 m; habit pyramidal to oval. Bark very thick, ash-gray, flaking to leave yellow patches, breaking into large plates. Branches whorled, upward-curving, esp. on young trees. Twigs twigs glaucous, turning brown at end of first year. Leaves in fascicles of 2, 6-11 cm long, 1.5 mm thick, stiff, sharp, green, in whorls about twigs, retained 2-6 years. Buds brown, not resinous, 15 mm diameter. Pollen cones bright yellow, in dense clusters at the base of the shoot. Seed cones in clusters of 2-4 on short peduncles, 7-9 cm long and 2.5 cm wide with a flat base and thin, weak scales, opening when ripe. Umbo very short, often missing. Flowers from May to June, cones ripening in September and October of the second year. Seed 7 mm long, with a wing 25 mm long (Farjon 1984, Janković 1986, Rushforth 1987, Richardson and Rundel 1998).

Var. leucodermis differs in being taller (to 30 m) with bark smooth and pale green-gray, later breaking into small plates. Young twigs are glaucous, white to grey-pink for three years, turning brown. Foliage is dark green. First-year seed cones are dark purple (Farjon 1984) or cobalt blue (Rushforth 1987).

Distribution and Ecology

Albania, Bosnia, Bulgaria, Greece, Macedonia and Serbia (Critchfield and Little 1966). Hardy to Zone 5 (cold hardiness limit between -28.8°C and -23.3°C) (Bannister and Neuner 2001).

The type variety is found in the W Balkan Peninsula (Silba 1986), including Albania, Bulgaria, Greece and Yugoslavia (Rushforth 1987), where is usually is found in mixed stands at 1000-2500 m elevation, reaching the alpine timberline amidst Pinus mugo (Farjon 1984, Richardson and Rundel 1998, Hristo Dimitrov Stankov e-mail 1999.06.30). Common associates include Pinus sylvestris, P. peuce and P. nigra (Hristo Dimitrov Stankov e-mail 1999.06.30).

Var. leucodermis is found in S Italy, Albania, Yugoslavia, and Greece, at 900-2500 m elevation on dry, sunny sites where it forms mixed stands with Abies and Fagus (Farjon 1984, Richardson and Rundel 1998), pure stands occurring only on steep and dry rocky southern slopes (Janković 1986).

Both typically occur on soils derived from calcareous (limestone, dolomite) or occasionally ultramafic parent materials. Together with Pinus mugo and P. uncinata, P. heldreichii is one of the high-elevation pines of the Mediterreanean basin (Richardson and Rundel 1998, Barbero et al. 1998).

Remarkable Specimens

I have seen a photograph (University of Aberdeen 1999) of a huge tree on Mt. Pindos in Greece that probably measures at least 220 cm dbh. A tree in the Pirin National Park, called Baikusheva mura or Baikushev's pine (photo) is 24 m tall and 222 cm diameter. Photos posted on Facebook by Luigi Ceci (2019.04.30, Big Tree Seekers group) show a very large tree that he reports "On the 'Pollinello', at 1,900 meters above sea level, in the territory of Castrovillari (Cs), a large pine tree of 12 m in height and 6.04 m circumference resists." This corresponds to a DBH of 192 cm.

The oldest known specimen is a tree of var. leucodermis that has been named Italus, growing in Pollino National Park in southern Italy (Piovesan et al. 2018). This has been described as the "oldest dated tree of Europe." The authors use a combination of evidence from tree-ring cores and sampling of old root wood to demonstrate that this tree was, when sampled in 2017, at least 1229 years old; their method of using root wood to extend the age estimate is the most scientifically innovative aspect of their work. The authors speculate (and I don't disagree) that this species should be able to survive to ages of as much as 1,300 years, and this accounts for the accounts of a "1300-year-old pine" that subsequently appeared in popular media such as newspapers and Wikipedia. Many of the same researchers have a long history of study of this species; as early as 1989, a specimen of var. leucodermis aged 963 years (in 1989) was collected on Mt. Pollino (approx. 39°50' N, 16°15' E). The specimen was cored ca. 1 m above ground level; most of the record was verified by crossdating (Biondi 1992).

For the type variety, the Baikushev Pine described above is popularly described as 1300 years old, but I have seen no data supporting that age estimate, and the tree does not look particularly old. An age of 1300 years would, perhaps not coincidentally, make the tree exactly as old as the nation of Bulgaria.

Ethnobotany

Var. leucodermis is a popular ornamental, with several cultivars in use (Rushforth 1987).

Observations

The Valia-Calda unit of Pindos National Park, in Greece, sounds like a good place to see the type variety; here it grows to the summit of Mt. Pindos, 2177 m. In Bulgaria it is native in Mount Pirin (also a good place to find Pinus peuce), where the entire population is protected within Pirin National Park; in this area it grows in forests with Pinus peuce. Pirin National Park is a remarkable place in general; with nine conifer species, it may host the greatest conifer diversity to be found anywhere in Europe. Farther south it grows on Mount Slavyanka, and is protected there in a Natural Reserve (Hristo Dimitrov Stankov e-mail 1999.06.30). The best place to see var. leucodermis is the Pollino National Park, which has adopted this pine as its symbol.

Remarks

The type variety is listed as vulnerable and var. leucodermis is listed as 'lower risk' by the WCMC (1998) database.

Named for its collector, von Heldreich, who found it in the mountains of northern Greece on July 31, 1851 (Christ 1863).

Citations

Anonymous. 1999. Parco Nazionale del Pollino. http://www.telsa.it/castrovillari/proloco/parco/parco.htm, accessed 1999.02.23, now defunct.

Barbero et al., 'Pines of the Medierreanean Basin', p.153-171 in Richardson 1998.

Biondi, Franco. 1992. Development of a tree-ring network for the Italian peninsula. Tree-Ring Bulletin 52: 15-29.

Christ, H. 1863. Uebersicht der Europaischen Abietineen (Pinus, Linn.). Verhandlungen der Naturforschende Gesellschaft in Basel (n. s.) 3:540-557 (p. 549). Available: www.biodiversitylibrary.org/item/100853, accessed 2011.05.20.

Hayter, Jane. 1994. Northern Greece. International Dendrological Society Yearbook, pp.104-124.

Janković, M. 1986. "Pinus heldreichii," in Flora Srbije. Belgrade: Serbian Academy of Sciences and Arts.

Kubler, Hans. 1991. Function of spiral grain in trees. Trees 5: 125-135.

Pino 1999 = Pino elicoidale (a Pollinello). http://194.243.119.70/pollino/pinoeli/pinoeli.htm, accessed 1999.02.23, now defunct.

Pino2 1999= Il Pino loricato. http://entoma.unibas.it/pinoloricato.htm, accessed 1999.02.23, now defunct.

Piovesan, G., F. Biondi, M. Baliva, E. Presutti Saba, L. Calcagnile, G. Quarta, M. D’Elia, G. De Vivo, A. Schettino, and A. Di Filippo. 2018. The oldest dated tree of Europe lives in the wild Pollino massif: Italus, a strip-bark Heldreich’s pine. Ecology 99(7):1682–1684.

University of Aberdeen. 1999. Untitled anonymous web site at http://www.abdn.ac.uk/~for284/pics/pic10.htm, accessed 1999.02.23, now defunct, however the information (and much more about P. heldreichii is now available at www.robolo.org, accessed 2021.05.13).

World Conservation Monitoring Centre - Trees [WCMC]. 1998. Database at http://www.wcmc.org.uk/cgi-bin/SaCGI.cgi/trees.exe, accessed 1998.10.01, now defunct.

Thanks to Milan Jovanovic for information and assistance contributed 1999.02.

See also

Elwes and Henry 1906-1913 at the Biodiversity Heritage Library (var. leucodermis, treated as P. leucodermis). This series of volumes, privately printed, provides some of the most engaging descriptions of conifers ever published. Although they only treat species cultivated in the U.K. and Ireland, and the taxonomy is a bit dated, still these accounts are thorough, treating such topics as species description, range, varieties, exceptionally old or tall specimens, remarkable trees, and cultivation. Despite being over a century old, they are generally accurate, and are illustrated with some remarkable photographs and lithographs.

Photo collection at Wikipedia Commons.

Description, reviews, and many photographs at www.robolo.org, accessed 2021.05.13).