1438 A NATIONAL PLAN FOB AMEKICAN FORESTRY 



even-aged stand and have in turn been followed by reproduction in 

 the openings and under the thinned stand. This process may have 

 been repeated several times, resulting in several distinct age classes 

 in the same area, sometimes in groups and sometimes with the younger 

 age classes forming an understory to the older classes. This two or 

 three-aged condition is very characteristic of the larch-fir forest. 



The customary cutting and horse logging in stands of this sort, 

 where small and large trees are intermingled, leaves standing a good 

 many unmerchantable trees and some small growth. During the era 

 of broadcast burning previous to 1925 in Idaho and before 1927 in 

 Montana, uncontrolled fire in the slashings was followed by the same 

 disastrous results as in white pine. Whether a single broadcast burn 

 is followed by reproduction depends on the severity of the burn and 

 the survival of possible seed trees. As a general thing, a great deal 

 of young growth and many trees under merchantable size are killed. 

 The dead trees subsequently make a veritable fire trap that becomes a 

 source of danger in the future protection not only of the originally 

 burned cut-over area, but also of adjoining virgin timber and cut- 

 over land. 



SLASH DISPOSAL 



As in the white pine forests, adequate slash disposal, followed by 

 intensive fire protection, is the key to keeping the larch-fir forest 

 reasonably^ productive. Under the present laws, slash disposal in 

 Montana is by spot burning and in Idaho by piling and burning. 

 As spot burning depends on cleaning up large natural accumulations 

 of slash, the result, even with careful execution, is the scorching and 

 killing of a good deal of young growth and small trees surrounding the 

 burned spots, leaving hardly more than half of the area in a green 

 and productive condition. If done under dry weather conditions, 

 spot burning often becomes a partial or complete broadcast burning. 

 Piling and burning, if carefully done, is expensive, and if carelessly 

 done it results in a broadcast burn. In general, no slash disposal at 

 all is preferable to broadcast burning. There are many large areas of 

 old cuttings in Montana in the neighborhood of Eureka, Kalispell, 

 and St. Eegis which have never burned and which are now, after a 

 lapse of 20 to 25 years, comparatively safe from fire and well stocked 

 with second growth. 



In the face of modern hazards, some form of slash disposal is 

 necessary. Partial disposal is the method recommended. The essen- 

 tial features of this method are piling and burning of slash only on 

 certain strips of about 100 feet in width, and intensive patrol of the 

 entire area of slashings for the 10 or 12 years required for natural 

 reduction of the risk through decay. The main objects of the cleared 

 strips are: (1) to reduce the chances of fires starting through human 

 agency on the traveled parts of the area; (2) to afford clear lines 

 from which fires can be fought; and (3) to break the area into blocks 

 in which such fires as may start can be isolated. The strips will cover 

 about 20 percent of the area under most conditions. 



COSTS 



The cost of slash disposal will range from 15 to 20 cents a thousand 

 feet of cut, including the charge for the 10 or 12 years required for 

 natural reduction of the slash as a menace. This is equivalent to 



