124 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



adopted is precisely similar to that carried out in New Zealand. 

 In humid situations very vigorous development follows from 

 coppicing, whilst seedlings respond to the increased light let 

 into the forest by judicious thinning. New South Wales in 

 particular is paying more attention to the perpetuation of the 

 more valuable hardwood forests by aided regeneration in the 

 form of thinning and ring-barking trees of little marketable 

 value, and fostering the development of young timber. 



Timbers for Telegraph and Trans??iissio?i Poles. — I had several 

 interesting discussions in New South Wales and Tasmania with 

 experts associated with the export of hardwood poles. On 

 submitting evidence of the premature decay in New Zealand of 

 imported poles the authorities were not surprised, as they 

 declared much of the timber was cut from comparatively 

 youthful trees of species not connected with the highest 

 durability tests, and, moreover, did not undergo any special 

 examination by the Government Expert Timber Officer. The 

 New South Wales Government has recommended that the 

 standard size of poles be increased to ensure the inclusion 

 of a larger proportion of heartwood. A further recommenda- 

 tion, and one that is worthy of adoption, is the purchase of 

 squared poles from which practically all the sapwood has been 

 removed. 



Ironbarks are always preferred for telegraph and transmission 

 poles, but to ensure identity a small piece of bark should remain 

 attached. The great demand for poles during the past few 

 years, however, has made it necessary to draw from other 

 species of gums. 



In Tasmania a system of cylindrical concreting the base of 

 the poles is being practised a good deal. Sapwood is removed, 

 and with the aid of a metal cylinder is substituted by a cement 

 covering that projects beyond the margins of the pole trunk. 



It is very evident that in constructing metal towers for the 

 support of over seventy miles of electric power lines from the 

 Great Lake to Hobart, the Tasmanian authorities had less 

 confidence in the suitability for the purpose of their own fine 

 hardwoods than those experts undertaking similar schemes in 

 this Dominion. 



