22 BULLETIN 1060, TJ. S. DEPARTMENT OF AGRICULTURE. 



the open, they' often dry sufficiently to be protected from attack the 

 following spring. Logs placed in water are safe from further in- 

 jury. Damage by these borers can be prevented almost entirely by 

 removing the logs from the woods or placing them in water as soon 

 as they are cut. 



Larger wood borers are an important factor in the deterioration 

 of the sapwood and heartwood of fire-killed trees and logs. During 

 the first two summers after the death of the trees or the felling of 

 ■ the trees the borers are most active, and at the end of the two-year 

 period the salvage value is usually next to nothing. If the logs 

 are placed in water or barked within a few weeks after cutting, losses 

 by these borers may be avoided. Logs which are loosely piled in 

 the open soon after cutting usually escape damage because of the 

 rapid drying out of the thin bark, which is then unattractive to the 

 borers for the laying of eggs. Dr. J. M. Swaine, of the Canadian 

 Entomological Branch, recommends covering the logs thickly with 

 brush. The logs to be covered should be piled on skidways and 

 given a very thick covering of green limbs so that the sunlight can 

 not penetrate at all to the logs beneath. 



WIND. 



Sitka spruce, because of its characteristically shallow root system, 

 can not withstand severe winds. Trees which grow on exposed 

 situations along the coast where they encounter severe winds are 

 windfirm, but they are also scrubby and of little use for lumber. In 

 the virgin forests under normal conditions only the very diseased 

 trees are likely to be windthrown, but in cut-over areas trees isolated 

 by logging and those which border on fresh cuttings are invariably 

 windthrown. (PL XVIII.) Spruce trees which have grown in 

 dense stands never become wind-resistant, and full consideration 

 must be given this fact before a method of cutting and a man- 

 agement policy are adopted for a spruce forest. 



The hurricane that swept the western edge of the Olympic pen- 

 insula, Washington, in January, 1921, felled from 5 to 95 per cent 

 of the timber on a swath 60 miles long and 20 miles wide in the 

 heart of the spruce belt. Six billion feet or more of virgin western 

 hemlock, Sitka spruce, Douglas fir, silver fir, and western red cedar 

 timber was laid flat by the wind. Perhaps a billion feet of Sitka 

 spruce in the State of Washington was windthrown in that storm. 

 All species suffered alike regardless of their relative windfirmness. 



In addition to windthrow, other damage from the elements is 

 wrought upon spruce timber by breakage and wind-shake. The 

 breakage consists in the shattering of the tops of overmature and 

 decadent trees, and this permits the entrance of fungous growth, 



