The fellows from 'Real SRT' are holding a workshop in Sydney on April 13th to try and open up our minds to the benefits of utilising SRT not just in tree access but throughout works. Really looking forward to this! if you are an Arborist in the Port Macquarie Hastings region or anywhere for that matter in NSW, get on down to Sydney town!
Off to Sydney for some Visual Tree Assessment training with the QTRA! After spending close to 4 years completing Cert 2-3-4-5 in Arboriculture, looking back I couldn't wait to leave the classroom behind. But now I CANT wait to put everything down and get back to the classroom and build up some additional knowledge!
In part 3.3.3 'Major encroachment' of the The Australian Standard AS4970 'Protection of Trees on Development Sites' it stipulates that;
"If the proposed encroachment is greater than 10% of the TPZ or inside the SRZ (see Clause 3.3.5), the project arborist must demonstrate that the tree(s) would remain viable. The area lost to this encroachment should be compensated for elsewhere and contiguous with the TPZ. This may require root investigation by non-destructive methods and consideration of relevant factors listed in Clause 3.3.4".
The team at E.A.R are currently working on a large scale tree protection plan and arboricultural impact assessment for a the site above, in which majority of the trees must be retained as they pertain high habitat amenity for the local Koala population. There are a number of homes in the plans which will encroach the TPZ by more then 10%, subsequently the E.A.R team spent Friday exploring root plates and carefully mapped the findings. These root map findings will help engineers to plan to avoid roots minimising the overall impact of the proposed development allowing the trees to continue to grow in a some-what altered environment which also complements optimum growing conditions.
If dealing with encroachments into the TPZ on any development site the following from AS 4970 is also extremely handy.....Remember once roots are severed the damage is irreversible and the affect can be life threatening to the subject tree. Initial tree management, sufficient tree protection measures with on going management by the project arborist can avoid unnecessary headaches and the trees amenity features will undoubtably complement the development.
3.3.4 TPZ encroachment considerations
When determining the potential impacts of encroachment into the TPZ, the project arborist should consider the following:
Great to see that the city of Melbourne are seriously making some plans to expand canopy cover of their already incredibly tree rich city.
Often misconceptions, bad advice and a lack of maintenance can lead to the destruction of many sound trees, seriously affecting local amenity. The urban forestry really has some unseen benefits which are hard to translate into a monetary value. If you are thinking of doing a large scale development or have concerns of a large/small residential tree, employ a local AQF 5 arborist to assist you with tree management options!
This film is truly incredible, unfortunately a lot of the larger forests and wood in Australia was taken out as a result of white settlement and the European way of life that came with it. This film focusses on the atmosphere of the forest as it was irrevocably changed by the axe and saw of the loggers in the Southern end of Western Australia. Its highlights the struggle that was associated with felling Jarrah and Karri forest in the Pemberton, transporting them to the nearby Pemberton sawmill, and milling the logs.
Enjoy an incredible piece of Australian tree working history, luckily enough to be captured by Bert Ive back in the early 1900's.
Really good clip detailing the steps involved in a Visual Tree Assessment VTA. Looking forward to going to Sydney in a few weeks to take part in the Visual Tree Assessment training which is being hosted by the QTRA (Quantified Tree Risk Assessment).
Decay in trees may not be as severe as you all think. Many other factors come into consideration such as target, occupancy, exposure and size/form of defective tree parts that may have a higher overall risk rating and have a higher chance of failure. Although the tree pictured above may be sheltered in a forest situation it is incredible to imagine the actual strength of the active tissue holding this huge Eucalyptus pilularis (Blackbutt) which dominates its immediate area. This tree among a few other giants is located on the 'Bird Tree' loop walk, 8kms west off the Pacific highway, 10kms South of Kew in New South Wales, Australia.
The first published guidelines for comparing stem failure in regards to decay were released in the early 1990’s. Mattheck, 1994, “The Body Language of Trees; A handbook of Failure Analysis”. Claus Mattheck proposed a .30 to .35 t/R ratio threshold of high risk of stem failure from a central column of decay for full crown trees. He noted that failures begin to accelerate in surveys, as the ratio begins to fall under .25 t/R. This became generally interpreted as a .30 t/R ratio or a 30% Remaining Wall!
The diagram above represents a 24” (inside the bark diameter), of a stem or branch, with roughly, a center column of decayed wood, (the diagonal lines). The t (above) is the outside shell of sound non-decayed wood. The diagram indicates that the internal wood decay has consumed roughly 2/3 of the cross-section. The t/R ratio is simply the ratio of the sound wood shell thickness (t), without the bark, to the radius of the cross section (R). The above example has a t/R ratio of 30%, or .30 or roughly 1/3 of the radius is sound! Guidelines for evaluating trees for decay!
Back in 2013 Mid North Coast Arborists held a 2 day training course for complex/confined tree removal in conjunction with a crane. As far as Im aware it was the first of its kind in New South Wales. Duncan from Mid Coast Crane had his 200 tonne crane in action and the 2 days really were a valuable learning experience, especially with Total heights Safety Bill Goddard training the crew. His expertise and tips were appreciated by each and every climber in attendance and I'm sure everyone walked awaywith some new found knowledge. In the picture bellow, Henk Morgans from Evergreen Tree Care which is based in Brisbane floats one away with ease.
Cheers to all involved. Looking forward to the 2015 climbing comp which is already in the works!