Periodical Literature 627 



seed for the private and communal forests since this would result 

 in destroying the business of the commercial concerns. Therefore, 

 State oversight of the firms seems the lesser of the two evils, 

 although it ^vill be difficult to manage it efficiently. 



Beschaffting von Kiefernsamen deutscher Herkunft. Forstliches Centralblatt, 

 June 1914, pp. 315-326. 



Carl Batz, in charge of a forest near the 



Damage by industrial towns of Barmen and Elberfeld 



Coal Fumes from which emanate large masses of coal 



smoke, warns against overrating the damage 



to forest properties, which there is a tendency to do. 



After detailing his observations in a long article, he draws the 

 following conclusions: 



Where there is much smoke there is damage. It is not, however, 

 stilfur dioxide which occasions the damage but higher oxidations, 

 which do not, as has been assumed, interfere with assimilation but 

 exercise a direct exterior influence. Snow, frequent mists and 

 slow rain are especially dangerous conditions, as they produce 

 accumulations of acid on the foliage, destroying it, especially at 

 time of budding. 



Topdryness or dead branches may or may not be caused by 

 smoke, nor is absence of vegetation on beech trunks a criterion. 



Soil-poisoning by sulfuric acid does not seem to occur, planta- 

 tions of broadleaf trees succeeding well, although it is possible that 

 the acid seeks to combine with bases and may absorb lime, and 

 also kill microbes. 



Conifers are most susceptible; among these most resistant are 

 Pinus austriaca and strobus with Picea sitchensis and Japanese 

 larch. Of broadleaf trees, oaks, Robinia, beech and birch are 

 most resistant. 



Tolerant species are not to be grown pure in smoke-infested 

 localities, since they cannot preserve favorable soil conditions — 

 the most important need. 



Wieler is quoted as doubting the influence of smoke on assimila- 

 tion and the propriety of determining damage by acid poisoning 

 because acid has been found in the analysis. 



Die durch Steinkohlenverbrennung am Walde entstehenden und vermuteten 

 Rauchschaden. Zeitschrift fiir Forst-u. Jagdwesen, March, 1914, pp. 158-174. 



