ANNUAL EXCURSION. 87 



to the community. This was sanctioned — Government ofFering^ 

 to contribute upwards of 50 % of the cost, the Canton of Berne 

 providing 20 to 30 %, while the remainder was made up by the 

 community. The community also undertook to maintain the 

 works. 



The Trachtbach rises at an elevation of 6068 feet, which is 

 rather higher than the tree limit in this locality. The physical 

 features of the valley show a series of gigantic steps. Operations 

 were commenced at the top and the work gradually proceeded 

 to the lower levels. A start was made by erecting parallel walls 

 of stone, the ground between which was then planted with grass 

 and trees. In the early stages of this work avalanches, which 

 formed in the spring of the year, very often swept away the 

 previous year's work. The mode of occurrence of these 

 avalanches is well demonstrated in Plate V. fig. 2. The pasture 

 which ultimately appeared on these upper slopes between the walls 

 attracted the flocks of the peasants, with the result that these 

 areas had to be rigorously enclosed. The tree species employed 

 in the plantings were Pinus Cembra, Scots pine, larch, spruce^ 

 mountain pine and alder, and they were put in in very small 

 groups. Experience has shown that at these high elevations 

 groups are better able to stand up against snow than single trees,, 

 and by having an exposed surface between the groups the soil 

 heats quicker under the action of the sun. Small nurseries were 

 established as high up as possible in order to save transport 

 and to acclimatise the young plants. Finns Cetnbra has probably 

 done best of all the species, as it has an extraordinary power of 

 recovery from snow-break, bruising, etc. Direct sowings were 

 tried in places but were not found to be successful. The grass 

 was established partly by planting squares of turf and partly by 

 collecting the seeds of the natural grasses and sowing them, 

 broadcast. 



As the work progressed modifications of the original methods 

 were made, the wall was discarded and gave place to a broad 

 terrace (Plate VI. fig. 5). These terraces are simply broad 

 drystone dykes which are topped with turfs. In localities where 

 stones were scarce wooden hurdles were erected and small 

 terraces of turf were built between (Plate V. fig. 3). 



As lower elevations were approached an extensive drainage 

 scheme became necessary. The waters from the melting snows 

 accumulated at the bottom of the topmost large natural terrace. 



