Bulgarian Fir Conservation status: Secure
Intact and disintegrated Bulgarian Fir cones
Scientific classification
Kingdom: Plantae Division: Pinophyta Class: Pinopsida Order: Pinales Family: Pinaceae Genus: Abies Species: A. borisii-regis
Binomial name
Abies borisii-regis Mattf.

Bulgarian Fir (Abies borisiiregis) is a fir native to the mountains of the Balkan Peninsula, in Bulgaria, northern Greece, Macedonia, Albania and Serbia. It is a large evergreen coniferous tree growing to 40-50 m (exceptionally 60 m) tall and with a trunk diameter of up to 1.5 m. It occurs at altitudes of 800-1,700 m, on mountains with a rainfall of over 1,000 mm.

The leaves are needle-like, flattened, 1.8-3.5 cm long and 2 mm wide by 0.5 mm thick, glossy dark green above, and with two blue-white bands of stomata below. The tip of the leaf is variable, usually pointed, but sometimes slightly notched at the tip, particularly on slow-growing shoots on older trees. The cones are 10-21 cm long and 4 cm broad, with about 150-200 scales, each scale with an exserted bract and two winged seeds; they disintegrate when mature to release the seeds.

It is closely related to (and in many respects intermediate between) Silver Fir to the north in central Europe, Greek Fir to the south in southern Greece, and Nordmann Fir to the east in northern Turkey. Some botanists treat it as a natural hybrid between Silver Fir and Greek Fir, while others treat it as a variety on Silver Fir, as Abies alba var. acutifolia. Another synonym is Abies pardei.

The scientific name honours Tsar Boris III of Bulgaria, during whose reign it was described as a new species in 1925.