Swiss Pine

The Swiss Pine or Arolla Pine, Pinus cembra, is a species of pine tree that occurs in the Alps and Carpathian Mountains of central Europe, in Poland (Tatra Mountains), Switzerland, France, Italy, Austria, Germany, Slovenia, Slovakia, Ukraine and Romania. It typically grows at 1,200 metres (3,900 ft) to 2,300 metres (7,500 ft) altitude. It often reaches the alpine tree line in this area. The mature size is typically between 25 metres (82 ft) and 35 metres (115 ft) in height, and the trunk diameter can be up to 1.5 metres (4.9 ft) .

It is a member of the white pine group, Pinus subgenus Strobus, and like all members of that group, the leaves ('needles') are in fascicles (bundles) of five, with a deciduous sheath. The needle-like leaves are 5 centimetres (2.0 in) to 9 centimetres (3.5 in) long. The cones, which contain the seeds (or nuts), of the Swiss Pine are 4 centimetres (1.6 in) to 8 centimetres (3.1 in) long. The 8 millimetres (0.31 in) to 12 millimetres (0.47 in) long seeds have only a vestigial wing and are dispersed by Spotted Nutcrackers.

The very similar Siberian Pine (Pinus sibirica) is treated as a variety or subspecies of Swiss Pine by some botanists. It differs in having slightly larger cones, and needles with three resin canals instead of two as in the Swiss Pine.

Like other European and Asian white pines, Swiss Pine is very resistant to White Pine Blister Rust (Cronartium ribicola). This fungal disease was accidentally introduced from Europe into North America, where it has caused severe mortality in the American native white pines in many areas, notably the closely related Whitebark Pine. Swiss Pine is of great value for research into hybridisation to develop rust resistance in these species.