76 



Canadian Forestry Journal, May-June. 1912. 



track. It' the fore:-t-lloor cover is only 

 slightly or with difficulty inflammable, it is 

 sufficient to keep bare a strip between the 

 right of way and the woods, so that a fire 

 starting caniiot jiass it; even this is some- 

 times not necessary as the light far-flying 

 sparks are not dangerous. 



Protection of Pine Forests. 



The conditions are quite different if the 

 railway crosses a wood with highly inflam- 

 mable ground-cover. There is especial dan- 

 ger for extended stands of pine on poor dry 

 soil. In such stands, the danger la'ts near- 

 ly all the year, and the flau'es, running 

 swiftly over the ground, easilv reach the 

 crowns; they are safe only as long as the 

 snow is on the ground, or as long as it is 

 raining. In these stands, as well as all 

 others, in which there is a large amount of 

 easily inflammable, dry material, special 

 precautions must be taken. Ordinarily the?e 

 consist of treeless spaces, which are either 

 used as farming land or planted with hard- 

 wood managed on short rotation. But on 

 dry forest soils, where the danger is great- 

 est, hardwood will not grow, and farming 

 does not pay, in which ease broad, entirely 

 unused strips are left on both sides of the 

 right of way, v.hich must lie plowed each 

 year, entailing expense and bringing no re- 

 turn, and sometimes also entailing danger to 

 the railway through drifting sand. 



Protection Strips. 



If these strips are needed to stop sparks, 

 they must be very wide. A width of ninety 

 feet on either side does not protect, for 

 Burkhard has observed that sparks have set 

 fire 240 feet from the track. But a strip 

 33 feet wide and a quarter of a mile long 

 contains one acre, therefore a strip 33 feet 

 wide on each side of the track would mean 

 eight acres per mile, not only lying useless, 

 but in some cases increasing the danger of 

 fire, as it has been proved that where a 

 railway runs through a forest which lies 

 close to the track, there the danger is, on 

 the average, less than when the woods are 

 farther away. If the trees are cloi-e the 

 wind is compelled to follow along the narrow 

 lane of the track, while if the trees are far- 

 ther away, the Mind can blow from the side 

 and drive the sparks among the trees." 



To overcome these disadvantages, and to 

 protect the forest from the danger of fire 

 from locomotive sparks, it is necessary to 

 manage the wood near the track, and to pre- 

 pare a strip on Avhich all fire will die out 

 before it can set fire to the crowns, or kill 

 the trees, and at the same time catch all 

 sparks. The glowing sparks are rather large 

 and fall inunediately to the ground as soon 

 as they strike the still air stratum inside 

 the protection stand, just as snow-flakes fall 

 behind a hedge or sand-clouds behind fences 

 an(l grass tufts. The protection strips, 

 which the author of this pamphlet has recom- 



uieuiled I'oi- pine forests of North Hnropean 

 plains, ansver a double purpose. They per- 

 mit the ute of woodland right up to the 

 track, even in districts most subject to 

 fires, protect the track from drifting sand, 

 and are relatively cheap to keep up. They 

 consist of strips of trees, 36 to 45 feet wide, 

 which have a bare ditch or path 4.-5 feet 

 wide toward the fores-t, and a strip. 3 feet 

 wide, of bare ground next to the track. The 

 two bare strips are joined by foot-paths, 

 kept bare, every sixty or ninety feet. 



As mentioned above, every fire starts from 

 a small beginning, which cannot harm the 

 trees, and is dangerous only when it has 

 succeeded in spreading, ^'ery often the dry 

 grass or moss on the railway embankment 

 catches, and has quite a large front by the 

 time it reaches the edge of the woods, and 

 that it may not spread over into the wood, 

 the edge of the wood is kej)t bare for three 

 feet. Then the fire goes out. The glowing 

 sparks which fall directly on the strips of 

 wood beyond the first bare place can start 

 only small fires, and if the^e spread, they 

 must die out on reaching the second bare 

 strip of 4.5 feet, or one of the cross lanes. 



Wooded Strips to be Narrow. 



Care must be taken that the fire on the 

 protection strips never reaches the size of 

 a crown fire, and thus spreads over the 

 bare strips. This end is achieved by the 

 narrowness of the wooded strips. If there 

 is not much fuel on the ground, a fire 36 

 to 45 feet from its origin is not high; 

 height comes only when a fire has reached 

 deeper into a forest, over a larger surface, 

 which much increases the heat. The amount 

 of inflauunable material on the protection 

 stand, both on the ground and above it, 

 must be kept down as much as possible ; all 

 dry brancdies, weeds, juniper and other in- 

 flammable objects nuist be removed; sup- 

 pressed and dry branches of the trees up to 

 breast-height must also be pruned off. Only 

 the green branches on the edges of the 

 stand must be ke})t as near the ground as 

 possible. The closer the green branches are 

 on the side toward the track, the better the 

 protection strip fills its second important 

 purpose, ie., to stop the lighter far-flying 

 sparks. 



To attain this end, the stand on the pro- 

 tection strips must be (dosed and without 

 large gaps; a stand which is too thick is 

 not favorable, for between the close stand- 

 ing trunks, the flames easily rise higher 

 thau where the trees are not so close, and 

 crowded trees do not develop gooil crowns. 



Since very old stands become too thin and 

 the high trees are likely to be thrown on 

 the tracks by storms, or at least may damage 

 the telegraph lines, it is necessary to choose 

 a short rotation for protection strips. In 

 determining this rotation, the first consider- 

 ation is the p)urpose of the protection 

 stands; the second is the yield. The rotation 



