REFORESTATION AREAS 425 



Climate. — The climate is very cold in the upper valley and cold in the lower parts. 

 On the summits the snow begins toward the end of October and persists until June. In 

 the bottom of the valley it generally lies from December to April. Because of its ex- 

 posure and its altitude the Blanche valley receives more rain than the south part of the 

 department of Basses-Alpes. Long droughts are rare. Storms are frequent in summer 

 on account of the nearness to the very high mountains. They have even the character 

 of veritable waterspouts and are very disastrous to the crops which occupy the lower 

 slopes and the bottoms of the valleys. 



Basins. — The mountains are covered with grazing ground and in many localities are 

 damaged on account of overgrazing. Every summer the ground is overstocked by 

 sheep and the easily erodable soil is bared and forms deep ravines. Coniferous stands 

 cover large areas and have a tendency to seed the neighboring bare ground. The 

 Scotch pine forms pure stands on south exposures and is associated with fir and spruce 

 on the moister slopes. On cold exposures these two species are frequently pure or in 

 mixture with beech. The mountain pine is also found. Beginning with 3,280 feet 

 altitude, there are stands of larch on the drier ground on north slopes. At very high 

 altitudes the cembric pine appears. The forests which are not subject to Federal con- 

 trol are exposed to destructive cutting and to intensive grazing, so that the soil becomes 

 impoverished and the stands become more and more open. The lower slopes and the 

 bottoms of the valleys are used for agriculture. Fruit trees are not over-abundant. 

 The cultivated land yields cereals and potatoes; the natural prairies occupy large areas 

 and produce a very valuable forage grass. 



Administrative Situation, Area, Population. — The Blanche basin extends over 

 one commune (la Breole) in the district of Barcelonnette and five communes in the dis- 

 trict of Digne. 



State of Soil Damage. — On all sides, but especially on south and west slopes, the 

 Blanche basin is cut by ravines of a torrential character, all more or less dangerous. 

 This damage has been caused by excessive grazing by cattle which has been too intensive 

 on all the uncultivated land. On account of its geologic constitution, the sub-soil, 

 formed either by black schists or by glacial deposits, is easily eroded after the cover 

 has been removed by sheep grazing. Besides, because of the very long and steep slopes 

 and on account of the abundance and frequence of snowfall and the rigor of the climate, 

 it often happens in spring that in the higher areas avalanches contribute to the destruc- 

 tion of the slopes. On certain areas the water filters into the soil and produces dangerous 

 landslides. 



Composition and Area. — The Blanche forestation area includes five working 

 groups according to the law of August 7, 1910. The total area amounts to 6,835 acres, 

 of which 3,623 actually belong to the State. 



Work. — The Seyne working group is composed, for the most part, by the old Seyne 

 area and some of the Colle, the reforestation of which aimed at preventing the recur- 

 rence of floods (produced by the overflow of the Blanche river) and at the extinguish- 

 ment of the torrents of Faut, Chateau, Allevar, Combanniere, and " Terre rouge." 

 They extend over the west slopes of a high chain of mountains which separate the 

 Blanche basin from that of Ubaye and are situated at altitudes varying from 4,590 to 

 8,200 feet. The work of control and reforestation was begun in 1862 and is still in 

 progress. At the beginning they proceeded simultaneously with sowing and planta- 

 tions of conifers and broadleaf trees, but it was not long before they found out that the 

 sowing generally gave poor results. . . . Accordingly plantations became the rule 

 except in special cases. The species used for the most part were larch, spruce, cembric 

 pine, mountain pine, Scotch pine, and Austrian pine. The larch was used in mixture 

 with the cembric pine in the highest zone, at an altitude between 6,560 and 8,200 feet, 

 on very steep slopes, covered with snow for the greater part of the year, and often 



