io6 Forestry Quarterly. 



The theoretical and practical aspects of the 

 Soil subject of mixed versus pure forests are 



Improvement discussed by Forstmeister D. Tiemann. 



in By way of introduction the author shows 



Mixed that the extensive forests of pure pine and 



Forest. spruce prevailing in many parts of Ger- 



many have come into being rather through 

 the influences of economic situations and through accident than 

 from the application of sound silvicultural principles. The im- 

 poverishment of the country by the 30 Years' War and later by 

 the Napoleonic wars, followed by the decline in the use of char- 

 coal, as mineral coal came into general use gave impetus to the 

 cultivation of valuable conifers in pure stands. This, coupled 

 with a lack of knowledge of the methods of regenerating mixed 

 forests, led to a decline in the cultivation of beech and some other 

 deciduous species. 



The cultivation of these pure coniferous stands, according to 

 Tiemann, is based not only on unsound biology, but on unsound 

 economic grounds as well. Pure coniferous stands, especially 

 if even-aged, are subject to many kinds of damage which are not 

 so severe in mixed forests. Snowbreaks, windthrow, fire, fungi, 

 and the ravages of insect epidemics do great damage in pure 

 stands; besides this, these lightneeding conifers are not only in- 

 different soil preservers but are actually soil robbers. 



Beech with its great tolerance of shade and its copious leaf fall 

 giving full protection to, and enriching the soil beneath may be 

 styled the nursetree of the forest and should be introduced where- 

 ever the soil fertility is endangered. An underwood of beech 

 beneath an open coniferous stand not only takes care of the soil, 

 and in so doing benefits the increment of the main crop, but is of 

 great value in aiding the cleaning process. 



Several methods of introducing the beech into gaps in spruce 

 and pine stands of advancing age are given, as well as for plant- 

 ing in the fail spots in young plantations. These methods all 

 necessitate the planting of groups large or small, or of strips of 

 beech, and, as this must be done by ball planting, are apt to be 

 rather expensive. 



In reforesting clearings, barren places, and wastelands, both 

 species may be planted by seed. In all such cases the beech is 

 planted in groups or strips from 6 to 10 years earlier than the 



