Pinus mugo, the Mountain Pine or Mugo Pine, is a high-altitude European pine, found in the Pyrenees, Alps, Erzgebirge, Carpathians, northern Apennines and Balkan Peninsula mountains from (mostly) 1,000 m to 2,200 m, occasionally as low as 200 m in the north of the range in Germany and Poland, and as high as 2,700 m in the south of the range in Bulgaria or in the Pyrenees .
There are major two subspecies:
- Pinus mugo subsp. mugo in the east and south of the range (southern & eastern Alps, Balkan peninsula), a low, shrubby, often multi-stemmed plant to 3–6 m tall with symmetrical cones.
- Pinus mugo subsp. uncinata in the west and north of the range (Pyrenees northeast to Poland), a larger, usually single-stemmed tree to 20 m tall with asymmetrical cones (the scales are much thicker on one side of the cone than the other). The two subspecies intergrade extensively (hybrid subspecies rotundata) in the western Alps and northern Carpathians. Some botanists treat the western subspecies as a separate species, Pinus uncinata, others as only a variety, Pinus mugo var. rostrata. This subspecies in the Pyrenees mark the alpine tree line or timberline, the edge of the habitat at which trees are capable of growing