DAMAGE CAUSED BY ATMOSPHERIC PRECIPITATIONS. 25 



and on the dead foliage still adhering to deciduous trees, not 

 infrequently freezing with a fall in temperature, and then offering 

 an increased foothold for further masses of falling snow, the 

 enormous burden thrown on the crowns of the trees becomes too 

 great to be borne. Wholesale damage can then often be caused 

 by the accumulations of snow either snapping off the tops of the 

 trees or breaking off the branches forming the crown, or else 

 simply throwing or crushing down the whole or a considerable part 

 of the crop, by reason of the enormous pressure exerted on the crowns. 



When branches, top-ends, or even poles and stems nearer the 

 base are snapped by snow, the damage is said to be done by 

 snow-break; but when the effects of the accumulations are, as 

 may often be noted in young plantations, even of species of trees 

 that are by no means easily thrown, to throw individual stems, or 

 whole patches, or larger portions of the crop to the ground with- 

 out breaking the bole, so that sometimes even the roots are drawn out 

 of the soil, the damage is said to be caused by snow-pressure. When 

 poles bending under a load of snow are burdened for some time with 

 the accumulation, they lose the power of recovering their original 

 upright growth, remain bent or crooked, and gradually die off. 



Snow-break occurs on single individual trees, or in patches 

 throughout the crop, whilst, on hillsides, lanes are sometimes 

 opened out by it ; but, as a rule, it occurs mostly in small patches 

 in the interior of forests, and on individual trees only near the 

 edges of the compartment. 



The damage wrought by such snow accumulations on a some- 

 what extensive scale are partly direct or immediate, partly 

 secondary or indirect. 



As direct or immediate consequences, may chiefly be noted the 

 interruption of leaf-canopy, and blanks formed in the crop, 

 with the loss of increment which is thereby entailed. The 

 damage done is, of course, the greater, the more the continuity of 

 the canopy is interrupted and broken, and not merely lessened in 

 density ; and the younger the crop is, the less will be the 

 returns procurable for the timber that will have to be extracted 

 and utilised. The damage can sometimes assume such propor- 

 tions that the whole of the immature crop may have to be 

 prematurely harvested. The growth of weeds and brushwood, 

 and the deterioration of the soil in consequence of the injurious 

 effects of insolation and winds on it, for the soil, no longer 



