Image of Potentilla aurea L.

Description:

Slo.: zlati petoprstnik, zlati prstnik - Habitat: Stony alpine grassland, road side, southwest oriented mountain slope; open, sunny and dry place; calcareous, skeletal ground, exposed to direct rain, elevation 1.860 m (6.100 feet), average precipitations ~ 3.000 mm/year, average temperature 0 - 2 deg C, alpine phytogeographical region. - Substratum: soil. - Comment: Potentilla aurea is a common and eye-catching plant of Julian Alps. Its numerous, deep yellow flowers are noticed from far. Yet, it has a close relative, namely Potentilla crantzii, which is very similar to it in habitus and flower size, shape and color and it is even more frequent. Both species grow in the whole Alpine belt and other European mountains. If one wants to distinguish between both, he has to look at their leaves carefully. They are generally similar too, but Potentilla aurea has long, half appressed, silky hairs along their edge. These hairs are often so dense that the leaves seem to have a silvery band all around, but sometimes they are not so conspicuous and a hand lens is of great help to see them. According to literature, there is another distinguishing parameter - size of the top-most, middle tooth of the serrate leaves. With Potentilla aurea it should be smaller than other teeth, while with Potentilla crantzii it should be of about the same size. But, to my experience, this trait is variable and one has to observe several leaves before making a decision. Also the yellow color of the flowers of the Potentilla aurea is deeper and more golden than with Potentilla crantzii. However, also here the flower color is variable and one needs some experience with both species to be able to differentiate them based on flower color only. - Ref.: (1) D. Aeschimann, K. Lauber, D.M. Moser, J.P. Theurillat, Flora Alpina, Vol. 1., Haupt (2004), p 772. (2) T. Wraber, 2 x Sto alpskih rastlin na Slovenskem, Preernova druba (2006) (in Slovene), p 81. (3) A. Martini et all., Mala Flora Slovenije, Tehnina Zaloba Slovenije (2007) (in Slovene), p 255. (4) M.A. Fischer, W. Adler, K. Oswald, Exkursionsflora sterreich Liechtenstein, Sdtirol, LO Landesmuseen, Linz, Austria (2005), p 483.