Periodical Literature. 263 



On overholders the increment may be considered by itself or in 

 relation to what (jverholders prevent by shading of the under 

 stand. Sometimes this outweighs the increment gained by the 

 overholders. In regeneration fellings, too, the opposite interests 

 of the young stand may make the light increment of the mother 

 trees illusory. But here the latter is to a certain extent incidental. 

 Where it becomes the object of management the young stand may 

 easily lose what the old trees gain. 



Regarding the amount of light desirable for regeneration, in 

 general for young plants full light is favorable, modified by the 

 necessity for protection against frost, drouth and weeds. 



In regard to soil, the matter is less simple- Dry turf (raw 

 humus) in dense beech and spruce stands on the one hand, and 

 weeds and heather on clear cut or open stands on the other show 

 the danger of both extreme darkness and extreme light. The 

 optimum lies between the extremes. For unhindered unlocking 

 of soil food is necessary a combination of light, air, warmth and 

 precipitation. 



Regulating the light supply in the stand, i. e. rearing the stand 

 is just as difficult and important as establishing the stand. The 

 ability to regulate the growing space of the usewood-producing 

 trees for the highest value production is more important and takes 

 more skill than the operations of culture and regeneration which 

 are principally matters of money. 



The knowledge required for this ability lies largely in the re- 

 sults of the many investigations into thinning and lighting. 



Finally, the speaker concluded, students, in your future ca- 

 pacities don't be mechanical. Strive always to use more and 

 more freely in the woods the productive powers of nature, not 

 the least of which is light. 

 Licht ist Leben ! 



Das Licht als Produktionsf actor in der Forstmirtschaft. Tharandter 

 forstliches Jahrbuch. 1912. Pp. 4-28. 



In Sweden the burning over of heaths as a 

 Fire precedent for cultivation has been con- 



as demned as deteriorating the soil, besides en- 



Means dangering the neighboring stands. 



of The Experiment Station has for a series 



Culture. of years investigated the question by means 



of a number of experimental plats (26) 



which are located on gravelly moraines on gneiss, which are cov- 



9 



