SULPHUK TRIOXID IN FOLIAGE OF TREES, ETC. 45 



was made that could not possibly have been killed by either of these 

 fires, as they had occurred too long ago, and, furthermore, the dying 

 trees were hardly scorched at the base. On the north side of Silver 

 Lake, also, the red firs were badly damaged and dying when this ex- 

 amination was made, and yet this region had not been attacked by 

 fire for many years. 



At the southern end of Georgetown Lake there did not appear to 

 be any injury to lodgepole pines or red firs on either the southern, 

 western, or eastern shores of the lake. To the north of the lake the 

 hills showed some dead red firs, but this section was not explored. 



In brief, it may be said that in the summer of 1908 the red firs 

 were injured for a distance of at least 15 to 19 miles north of smelter, 

 for IH to 14 miles east of it (where the damage from the Washoe 

 smelter and the Butte smelters probably overlapped), for 10 miles 

 south, and for from 18 to 19 miles west of the smelter. The injury to 

 lodgepole pines extended for a distance of at least 10 to 11 miles 

 north of the smelter, 9 to 10 miles south of it, and 10 miles to the west. 



SULPHUR TRIOXID IN FOLIAGE OF TREES AROUND WASHOE 



SMELTER. 



The samples of injured foliage near the smelter and of uninjured 

 foliage of the same species of trees beyond the apparent range of 

 damage collected on the trips just described were examined for sulphur 

 trioxid and ash and the results compared, as in the previous investi- 

 gations around Anaconda. Samples of soil beneath the injured and 

 uninjured trees were also examined to determine whether or not any 

 increase in the sulphur trioxid content of the injured trees might be 

 due to a larger amount of this constituent in the soil. The results 

 obtained are given in Table XIII, which shows that the soils near the 

 smelter contained in nearly all cases practically the same amount of 

 sulphur trioxid as those beyond the range of apparent damage. It 

 is not necessary, therefore, to take the soils into consideration in 

 comparing the injured with the uninjured trees. 



