66 REPORT OF THE FOREST COMMISSION. 



W hat a Fire Line Is. 



As interest in these fire lines is still active, while knowledge 

 of their construction and specific objects is limited, the follow- 

 ing description from last year's report is here reproduced : 



Figure 12 shows in a diagramatic way the essential features 

 of a railroad fire line constructed on level ground. Many people, 

 including some railroad superintendents, think that the best fire 

 line is one which is entirely clear of trees for a width of not less 

 than 100 feet. If the ground could be entirely bared, and kept 

 so, that would be true, but since weeds, sprouts and a variety of 

 growth could not be suppressed at a reasonable cost, it is much 

 better to allow trees to stand at intervals over the greater part 

 of the danger zone because their crowns interrupt falling sparks, 

 and in many cases may prevent such sparks from reaching the 

 inflammable material on the ground until they have lost their 

 power to ignite it. 



The essential features of the fire lines as required in this 

 State are: A safety belt, or bared strip, ordinarily 10 feet wide 

 and usually 100 feet from the nearest rail of the track. This 

 safety belt serves in a way as an automatic fire check. From 

 its whole length and width every particle of vegetation and in- 

 flammable matter is to be removed and the mineral soil exposed, 

 and so maintained. Between the safety belt and the roadbed 

 lies what is called the danger zone, usually 100 feet wide. Here 

 the ground is simply cleared of grass, brush, etc., by mowing or 

 burning, or both, and the trees where they form thickets are 

 thinned out. There is no need to remove any tree of fairly 

 good form unless it crowds closely upon several others, but all 

 trees which remain are trimmed of branches to a height of 6 

 feet. 



If a spark is thrown from a locomotive stack beside one o*f 

 these fire lines the interference of the standing trees will prob- 

 ably so retard its fall that its igniting power is lost; but if a 

 spark is not so killed it is practically sure to fall inside the safety 

 belt. There it finds little to burn, and if some grass or dry leaves 

 are ignited the fire can gain little force or headway before it 



