Small, thin trees that are usually removed from forest plantations to make way for larger trees could help meet the growing demand for power poles, street lighting and signage posts. The Queensland Department of Agriculture, Fisheries and Forestry (DAFF) is seeking commercial partners interested in producing power poles made from these plantation “thinnings”. Sources: Queensland Country Life, The Gympie Times
These “thinnings” can be used as an alternative to the traditional, declining source of hardwood power poles from native forests. Dr Henri Bailleres from DAFF said there were more than five million timber power poles in use in Australia.
“As the power network expands, we need more new poles and replacements for old poles that have stood for up to 60 years,” he said. “In Queensland, several hardwood species growing in plantations with great strength and durability would be suitable for use as utility poles, even at a very young age.
“DAFF forestry scientists have developed a new pole system that uses these young hardwood plantation thinnings.
“The thinnings, which would otherwise be wasted, can be combined to make power poles just as strong and long-lasting as single trunk poles.”
Dr Bailleres said the hybrid utility pole’s design consisted of a central steel spike in the ground to which three to four thin hardwood stems are bolted to the above ground part of the spike.
“This simple design is just as strong as a traditional pole made from a single, large-diameter tree,” he said. “This system could not only meet the demand for power poles, but also significantly boost the profitability of hardwood plantations by generating revenue early in the plantation lifecycle.”
“We are seeking industry partners to develop the pole system to meet precise industry requirements,” he said. “One of the advantages of this new system is that the timber components are positioned above ground level, away from the high-decay zone in the ground.”
With a lower risk of decay, the new utility pole system could potentially provide longer service life than traditional timber poles.
This approach also eliminates the need for metal-based, in-ground chemical treatments. Completely organic above ground preservative systems will provide adequate protection, and the timber thinnings are easily accessed for routine inspections.
The central spike can be made from galvanised mild steel or from stainless steel where an extended service life is required, or where there are harsh soil conditions.
The next step in development is to bring companies onboard to test the idea.
