PERIODICAL LITERATURE 647 



5. The resin yield can be considerably increased through continual 

 scarification if the progress is correctly made, namely, upward. 



6. The weather limits the beginning and end of the yearly utilization 

 as well as the intervals of the single harvests during the season ; with 

 favorable weather — ^warm but not dry — in middle and late summer a 

 return within two or three days may be maintained ; the rule is that 

 pauses of three to four days — twice weekly — should be maintained. 

 At the beginning and end of the period the pauses should be still 

 longer. 



7. If a large circumferential surface is scarified, as well as in the 

 case of deep cuts, longer pauses must be made between the single cuts. 



8. The more fully crowned side of the tree, more accessi])le to the 

 light, is as a rule richer in resin ; on leaning stems it is the upper side, 

 which is also preferable on account of the more favorable exterior run 

 of resin. 



9. The most profitable method of scarification consists in oblique, 

 slightly slanting, troughs which utilize half the stem circumference, 

 beginning at the very base of the stem and progressing in as small as 

 possible or no intervals upwards. 



10. The cuts are to be made narrow and shallow. Opening of old 

 cuts damages the total yield especially if repeated ; the same holds true 

 for the simultaneous making of several cuts above each other. 



11. The best collecting is done by a flower-pot like pot fastened 

 with a large nail and provided with a broad dropping tin. 



12. If the part of the stem which can be reached without ladder has 

 been used up and the stand is soon to come into utilization, it might 

 be suitable to turpentine the other side of the stem. A diminished 

 yield in the beginning is to be expected but must not deter the utiliza- 

 tion. In this way stands are to be turpentined for from four to six 

 years ; in stands which are to be cut in one or two years after the 

 beginning of the turpentining two-thirds or three-quarters of the cir- 

 cumference may be turpentined. B. E. F. 



Harzmitcung dcr Fochrc. Naturwissensch. Zeitschrift fiir Forst und Land- 

 wirtschaft. Oct.-Dec, 15)19, pp. 2S1 -;]()■). 



During the war a method was devised by 

 Turpentine Oil which pine lumber can be dried in three days. 

 and Rosin The process yields a considerable amount of tur- 



pentine and rosin as by-product. The total pine 

 wood cut each year in (k-rmany could yield some 378,000 metric tons 

 of extract, of which about one-fourth would be oils, the rest turpentine 



