Variation of cone characters in Pinus mugo (Pinaceae) populations in the Giant Mountains (Karkonosze, Sudetes).

The subalpine communities of Pinus mugo were destructed and replaced by pasture lands on plateau parts and moderately inclined slopes of the mountains during between the 15th andthe 18th centuries. The species were able to survive that pressure probably on the abrupt slopes of the glacial cirques. The pasturing stopped in the 19th century, andthe mountain pine started to reforest its previous habitats since that time. It was also plantedin several places and some of contemporary populations can origin from the seeds of the Giant Mountains. In the latter case the populations on the plateau shall reveal differences in the cone characters from autochtonous ones from the glacial cirques. This study was structured on this hypothesis. The characteristics of seven Pinus mugo populations in the Giant Mts. were comparedon the basis of 15 morphological characters of cones. Each population was represented by at least 30 individuals, and for every individual 10 cones were examined. Four of the sampled populations, treated as local, occurred on the steep slopes of the glacial cirques andthe other three on the mountain plateaus, use das pastures in the 17th to 18th centuries, potentially originated from another region. Results show rather small differences among the compared populations, independently of origin. The separation of the plateau from the steep slope ones is rather inconspicuous, if any. This suggests the local origin of plateau populations, even when planted. [ABSTRACT FROM AUTHOR]