I don't know, but what Sepp describes sounds like a tree/bush/shrub.
That looks like groundcover to me.
Wondering if this is it
Salix hegetschweileri
Here is a list of Alps Salix that I found
http://www.naturetrek.co.uk/reports_new/CHE02_report_080615_Wengen_Alpine_Flowers_of_the_Swiss_Alps.pdf
Salix aurita Eared Sallow
Salix breviserrata Finely-toothed Willow
Salix foetida Above Grutschalp
Salix hastata Large-stipuled Willow Lauberhorn
Salix glaucosericea Silky Willow Lauberhorn
Salix hegetschweileri Alpine Willow
Salix helvetica Swiss Willow Planted. Murren
Salix herbacea Least willow
Salix laggeri Lagger's Willow
Salix myrsinites Whortle-leaved Willow
Salix reticulata Net Leaved Willow
Salix retusa Retuse-leaved Willow
Salix serpyllifolia
Salix viminalis Osier Occasional. Riversides