Periodical Literature 253 



reached a height of 3 to 6 feet and produce the desired mechanical 

 influence in retarding the waterflow and binding the soil, accumu- 

 lating silt. 



Some 400 acres have been planted in this way during the last 

 15 years ; not more than 20 to 30 per cent of the plants being 

 lost as against 40 to 50 per cent when planted at wider spacing, 

 and due to the frugality of the species the plantations are aston- 

 ishing. The development of mycorhiza is specially prominent in 

 this poor soil. 



This alder, to be sure, can only be used for coppice growth, 

 but as first cover and nurse for more valuable species to replace it, 

 it has proved invaluable. 



As soon as 4 to 8 inches of silt has accumulated, prolific root 

 formation takes place and the soil accumulation from overflow 

 increases in a few years to 20 and 40 inch depth. 



Weisserle und Tessinkorrektion. Schweizerische Zeitschrift fiir Forstwesen, 

 December, 1914, pp. 307-314. 



Some years ago Nils Sylvan found that 



Groivth Rate in the same stand Norway spruce developed 



and side by side diflferent branch systems, of 



Branch Form which he recognized five, and suggested that 



in these forms diflfered also in silvicultural 



Spruce characteristics due to the difference in 



light condition which the different forms 



enjoy, the exposure of the foliage varying. Now by a careful 



investigation on over 3,500 spruces he has established the fact that 



the rate of growth and hence the volumes, vary in these diflferent 



forms. 



He recognizes five branching types; namely, (a) the pure comb 

 type with regular long pendulous side branchlets looking like the 

 teeth of a comb; {h) the irregular comb type with shorter, irregu- 

 lar yet comb-like side branchlets ; (c) the band or ribbon type with 

 short flat branched main branches, ribbon-like; {d) the broad 

 flat (Flatten) type with spread out ramifications; {e) the brush 

 type with close short ramifications, especially of the upper 

 branches giving a brush-like appearance. 



Even-aged, contiguous, uniform stands were selected for 

 measurement. As a rule, the brush type was in great majority, 



