Abies × borisii-regis
King Boris Fir, Bulgarian Fir, Macedonian Fir; Българска ела [Bulgarian]; makedón jegenyefenyő [Hungarian].
Syn: A. alba var. acutifolia Turrill; A. alba ssp. acutifolia (Turrill) Fukarek. Type locality in the Rodopi Mts about 50 km SW of Plovdiv, Bulgaria (Liu 1971).
Since the analysis by Liu (1971), this species is generally regarded as of hybrid origin, originating from introgression between A. alba and A. cephalonica, as detailed by Mitsopoulos and Panetsos (1987). Rushforth (1987) considers that it is "better understood as part of the group from which all these species [European and SW Asian Abies] have separated" rather than a recent hybrid; this view is supported by the presence of trees in the wild in Bulgaria with some foliage characters resembling A. nordmanniana (Frankis 2001).
Tree up to 45(-60) m tall, trunk to 1.5(-2) m dbh (Frankis 2001). Shoots light yellow when young, with scattered to dense short brown hairs 0.5-1 mm long (Vidakovic 1991); shoot buds ovoid-conic, 3-6 mm, brown, without resin or with a thin coat of clear resin (Frankis 2001). Leaves acute, occasionally with rounded or notched apex, 2-3 cm long, 2-3 mm broad, densely arranged, pectinate below the shoot, across the shoot above or (on heavily shaded shoots) also pectinate above as in A. alba; either without stomata or with a small patch of stomata near the tip on the upper surface, and with 2 white stomata bands on the lower surface (Vidakovic 1991, Frankis 2001). Cones very similar to A. alba but often longer, and to A. cephalonica; cylindrical to narrow conic, 11-21 cm long, 3-4 cm broad, green tinged pink or violet before maturity (Frankis 2001). Cone scales short tomentose, 3-3.5 cm wide, 3-3.5 cm long; bract scales 3.5 cm long, exserted 5-10 mm with a reflexed aristate tip; seeds12 mm long, with a 20 mm wing (Vidakovic 1991, Frankis 2001).
Bulgaria, N Greece, Albania, and the former Yugoslavia (Vidakovic 1991), at elevations of 700-1700 m in the Pirin Mtns. of SW Bulgaria (Liu 1971, Frankis 2001) and to 1800 m in Greece (Liu 1971). Hardy to Zone 6 (cold hardiness limit between -23.2°C and -17.8°C) (Bannister and Neuner 2001).
Trees 60 m tall grow in the Rilski Manastir Reserve, Rila National Park, Rila Mts, Bulgaria - the tallest trees of any species in Bulgaria (Anton Antonov, pers. comm. to M. P. Frankis in Bulgaria, 2001.09).
A tree-ring chronology covering 170 years, presumably based on living tree material, was collected in 1996 at Panetolikon-Oro, Greece (1350 m elevation, 38° 43'N, 21° 40' E) by F.H. Schweingruber (NOAA 1999). Very few collections of this species are recorded and substantially older trees may occur.
Named in honor of Tsar Boris III of Bulgaria (1894-1943, King of Bulgaria 1918-1943).
Pietro Paolo Adinolfi (e-mail 1998.01.11) reports: "Some months ago I met Dr. Arsen Proko from Tirana University. He showed me slides about Abies borisii regis. He doesn't think it is an hybrid. This abies has a particular character which isn't in Abies alba and in Abies cephalonica. If you cut a tree there will be suckers [perhaps sprouts?] from the stump." This report could not be confirmed by Frankis (2001).
Frankis, M.P. 2001. Field notes, Bulgaria, September 1998 and September 2001.
Mitsopoulos, D.J., and C.P. Panetsos. 1987. Origin of variation in fir forests of Greece. Silvae Genetica 36(1):1-15.
NOAA Paleoclimatology Program Tree-Ring Data Search Page. 1999.02.24. Results of database search. URL: http://julius.ngdc.noaa.gov/paleo/ftp-treering.html.
Thanks to Michael Frankis for extensive revisions to this page, 2002.01.
Last Modified 2012-11-28