108 Forestry Quarterly 



ing and otherwise so that it can be asserted, soil conditions in many 

 German forests have improved through change to a clearing system 

 and planting of pine. The city forest of Zurich is also cited, where 

 a clearing system has been in vogue four centuries and soil con- 

 ditions are mostly excellent. 



The claim that selection forest on account of the protection of 

 the soil was a better producer could also not be maintained; the 

 retardation under the shade in the early development is never 

 lost ; the form of the crown in the selection forest is not as favor- 

 able to the utilization of the light as the less spreading, conical 

 crown of the timber forest. Spruces with their slender, conical 

 crown in close crown cover at 30 to 50 years can produce up to 

 425 cubic feet per annimi, more than any figures reported from 

 selection forest; the average production in the Swiss hill country 

 is 256, 215, 172, 143 cubic feet for the four site classes, as good a 

 product as any selection forest. 



Similarly, the value production, if average conditions are taken 

 and not only the best trees, lags behind the timber forest; more 

 taper, more branchwood and knotty material balance the possibly 

 greater diameter development. 



Nevertheless, selection forest may be managed profitably under 

 favorable conditions; both volume and value increment in the 

 young age classes being very small, due to suppression, they im- 

 prove in later life, so that at 120 years with 12 inch diameters the 

 two increments present still 5 per cent and at 140 years with 16 

 inch diameter still about 4 per cent. 



While economic considerations will hardly lead one to the 

 selection forest, its undoubted value lies in its resistance to dam- 

 age by wind, snow, frost, fire, etc. 



Judgments on the value of these methods of management can, 

 however, have no general value; they can have reference only to 

 given cases and conditions. Admitted must be that in Switzer- 

 land the moments which condition the selection forest are much 

 more strongly present than in Germany. 



In similar fashion, Dr. Martin discusses the practices of Swiss 

 foresters in regeneration, species by species. A consideration of 

 the question whether natural regeneration or artificial reforesta- 

 tion is preferable leads to a cautious r^sum^. 



To secure satisfactory natural regeneration, certain conditions 

 must exist; if they do exist then this regeneration is in every 



