42 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL S0CIP:TY. 



at which the attack was growing in force, and were thus able to 

 adopt preventive measures before it was too late. Whenever 

 over I GO to 150 eggs were found on a spruce and over 1 50 to 200 

 on a pine grease-banding was undertaken, and this system, 

 thoroughly carried through as it has been, has probably alone 

 saved Saxony from what might easily have been a disaster as 

 far as the forests were concerned. Probably few of the German 

 States offer such a suitable breeding-ground for the Nun moth as 

 Saxony, with its large extent of pure spruce forests ; and it is 

 undoubtedly a great achievement, worthy of the forest service, 

 that their efforts in preventing a serious calamity have met with 

 such success. Since the commencement of the attack (1904-6), 

 which is now passing away, 50,000 acres have been completely 

 grease-banded at a cost of about eight shillings per acre. Better 

 and more economical methods have been devised for the applica- 

 tion of the grease during this period, as special attention has 

 been given to this detail, and at present the method generally 

 adopted is "high banding," with the aid of 12 ft. ladders. The 

 actual instrument now exclusively used for applying the grease 

 is that invented by Max Janke, which is a great advance on any 

 previous appliance, and the use of which has materially reduced 

 the cost of the process. The instrument is light, handy and 

 inexpensive, and can be worked with one hand, being thus 

 particularly adapted for high banding which by its use can 

 be carried out almost as cheaply as low banding formerly. 

 The reason for this is partly that the bark on old trees is much 

 smoother where the high band is applied and does not require, as 

 a rule, to be scraped, which saves almost as much time as is re- 

 quired to manipulate the ladders. Of the eight shillings per 

 acre which the process costs, five shillings go in labour at about 

 fourpence per hour, and the remaining three shillings represent 

 the cost of the grease which at •82d. per lb. = 44 lbs. per acre. 



The natural enemies and parasites of the Nun moth have 

 helped considerably in suppressing the attack. Among these 

 Parasetigena segregata took a leading place, but curiously enough 

 it increased to such an extent in some Rcviere that it became, 

 unfortunately, itself the host of another parasite Anth-ax viorio 

 {Diptera), which in no small degree checked its good work. 

 The attack, which is now passing away, centred itself on certain 

 spruce and pine woods in the dry flat country to the south-east 

 of Leipzig. Since the outbreak started a great deal of research 



