SOME VEGETATION TYPES AT HIGH ALTITUDES. 5 I 



(erect form) association. Small forest clearings occur in places, 

 and are very characteristic of this class of forest, especially 

 where larch is abundant (PI. III. fig. 8). The undergrowth 

 is very sparse and consists mainly of juniper {/uniperus 

 communis). Approaching the lower limit Pinus Cembra 

 is replaced by spruce {Ficea excelsd) and Scots pine {Pinus 

 silvestris), together with Pinus silvestris var. Engadinensis. 

 Occasional specimens of the erect form of mountain pine also 

 occur in this forest zone. Thus larch, spruce and Scots pine 

 form the mixed coniferous forest of this region. The forests 

 in the vicinity of Zernez form an excellent example of such a 

 mixed forest. 



The following broad-leaved species occur in the above asso- 

 ciation: — Aspen {Populus iremu/a), rowan {Sorbus aucuparia), 

 Sorbus ChamcBtnispihis, and birch {Betula pubescens). In the 

 undergrowth, juniper, barberry {Berberis vulgaris), Lonicera 

 nigra, L. ccerulea, and willow (Sa//x cinerea) make their appear- 

 ance. The ground vegetation, which in the upper stretches of 

 the zone has complete possession of the soil, has not such 

 a robust development towards its lower limits owing to the 

 presence of spruce. This ground flora consists chiefly of the 

 following : — Rhododendron hirsutum, Daphne striata, D. mezereum, 

 Vaccinium vitis id<za, Pirola unifiora, P. media. Erica carnea^ 

 Calluna vulgaris, Melampyrum silvaticum, M. prafense, LinncBa 

 borealis, Deschampsia C(zspitosa, Sesleria ccerulea, etc. 



Some of the tree types of the mixed coniferous forest associa- 

 tion are of special interest, for example, Pinus silvestris var. 

 Eftgadineftsis, which is an important constituent of this forest 

 2one. It diff"ers in many respects from Pinus silvestris as we 

 know it in Scotland. In growth habit it is tall and somewhat 

 pyramidal, the side branches are comparatively slender, and 

 the crown has no tendency to have a wide umbrella -like 

 expansion. The crown is rather deeply set, and altogether of 

 a loose, open nature, since the whorls of branches are widely 

 spaced. As a result of this open formation of crown it suff'ers 

 much less from snowbreak than the common variety. The red 

 copper-colour of the bark of the crown branches, so character- 

 istic of the common variety, extends practically to the foot of 

 the tree in variety Engadinensis. The bark in quite old trees 

 is neither so thick nor so much fissured as that of the common 

 variety. The duramen even of large stems is light red to 



