DAMAGE DONE. 641 



soil-denudation when it is followed by heavy rain ; this was 

 the case in the Siwalik hill-range, extending over fifty miles 

 between the rivers Ganges and Jumna, and its protection from 

 fire was demanded in 1882 by the Indian Irrigation Department 

 to prevent their canals from silting up. Some American forests 

 are so seriously injured by fire, that rainwater passes over the 

 soil, as over a roof. Observations have shown that up to 90 

 per cent, of the rainfall runs over the surface of burned forests 

 and fills the watercourses with silt and other debris. 



There is an increased tendency to breakage and to damage 

 by insects, also to growth of weeds and consequent increased 

 cost of sowing and planting. Fires are extremely injurious in 

 forests on shifting sands. 



After fires in Scots pine woods, the following insects may 

 become extremely abundant and destructive : Myciophilus 

 inmpcrda, L., in England and German}^, in Germany only, 

 Pissodes notatus, Fabr., Tomicus hidens, Fabr., T. Laricis, 

 Fabr., HyUistes palliatns, Gyll., and Hylurgus minor, Hrtg., 

 Mi/elop]iilus minor, Hrtg., etc, 



b. According to species. 



In Central Europe, conifers suffer much more than broad- 

 leaved species from fire, owing to their resinous nature, and to 

 the inllammable evergreen needles, which favour the spread 

 of the fires. The Scots pine and the Austrian pine are the 

 most exposed to danger. Other pines, such as Weymouth 

 pine, are grown only to a limited extent, or, as in the case of 

 Cembran and Mountain pine, they grow* on high mountains, 

 where fires are less dangerous. The greater danger the Scots 

 pine experiences from fire is due to the early drying up of its 

 lower branches and to the dry nature of the soil-covering, 

 owing to the imperfect leaf-canopy of this tree and to the 

 nature of the localities (heather lands) on which extensive pine 

 forests occur. In France, the forests of maritine and Aleppo 

 pines are specially liable to fires. 



After pines, come in point of danger, first, the spruce, then 

 silver-fir, and lastly, larch, owing to its being a deciduous 

 tree. 



F.P. T T 



