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What’s under the Skirt? Dead Washingtonia leaves as habitat for birds and bats.

Cultivated in Australia since the 1880s, the two North American fan palm species, the Californian Fan Palm (Washingtonia filifera) and the Mexican Fan palm (Washingtonia robusta) are a common sight in many Australian communities. The palms go under various colloquial names. W. filifera is known as ‘sky-duster palms,’ ‘’railway palms,’ ‘desert fan palm,’ ‘American cotton palm,’ ‘petticoat palm’ (because of the ‘skirt’ of dead leaves that cover the stem) and while W. robusta is known as ‘Washington palm,’ ‘Mexican washingtonia,’ ‘Cotton Palm’ and also ‘sky dusters.

As these palms were widely marketed by the horticultural trade they now have a global distribution. A systematic review of the ecological provisioning services provided by these palms has shown that their drupes (fruit) are consumed by a wide range of birds, fruit-bats and terrestrial animals. While coyotes are the main disperser of seed in the palms’ original distribution range of Southern California and northern Mexico, many native species in other countries have adapted to feed on the fruit offered by these exotic palms.

Little is known about the animals that feed on the palm fruits here in Australia. On record are only Pied Currawong, Starlings and Blackbirds, as well as fruit bats, but there are bound to be many more bird species that eat the fruit.

Even less is known about what goes on under the ‘skirt’, the array of dead leaves at the bottom of the crown of both species. These dead leaves persist in particular among W. filifera as well as the hybrid Washingtonia X filifera, unless they are arboriculturally removed for aesthetic reasons or because they pose a fire risk. In the southern USA, a wide range of birds (among them sparrows, owls and parakeets), small bats as well as rats use these leaf thickets as nesting and roosting habitat. In Europe, feral parakeets and rats have likewise colonised these spaces.

In Australia nothing is known about what goes on under the ‘skirt’ of our palms, despite the palms being so wide spread. Arboriculturalists are uniquely placed to assist, as they are regularly engaged in the pruning and tidying up of these palms. Many will have noted wildlife or evidence of its activities, but not thought it worthwhile to photograph or record it.

We would like to hear from you. Next time you are pruning, or removing, Washingtonia, look under the skirt and tell us what you find.

For more information and to assists with this research please contact A/Prof Dirk HR Spennemann, Institute for Land, Water and Society; Charles Sturt University; PO Box 789; Albury NSW 2640 or via email at [email protected]

October 21, 2019 / by / in , ,
Goodbye African Tulip

Spathodea campanulata may be a treasured tree in its native homeland of Africa but, in Australia, it is a tree no longer welcome.

Once a popular ornamental tree, African Tulip was widely planted in yards and along footpaths for its shady rounded canopy and showy bright orange-red flowers.

Biosecurtiy Queensland deemed the African Tulip a serious environmental weed way back in 2003 due to its aggressive growth and ability to spread into natural areas.

Its long, horn-shaped seed capsules can hold up to 500 papery seeds with transparent wings. If this is not enough, the tree also has suckering abilities.

There were consultations with the Nursery & Garden Industry Australia (NGIA) and it was agreed the tree must not be given away, sold, or released into the environment without a permit. Nurseries or market traders in Queensland that sell African Tulips may have their stock seized and destroyed, and re-offenders fined.

The Biosecurity Act 2014 requires everyone to take all reasonable and practical steps to minimise the risks associated with invasive plants and animals under their control. Councils in Queensland also have an obligation to remove African Tulips from the landscape.

“The public has become more enlightened about the importance of taking care of our native bee populations, and that is providing motivation to remove weed trees such as the African Tulip.”

Many councils are replacing them with native species as part of staged work programs in natural areas, parks and streets, and property owners are encouraged to do the same voluntarily.

Recommended non-invasive native alternatives to the African Tulip ar Stenocarpus sinuatus (Wheel of Fire) and Brachychiton acerifolius (Illawarra Flame Tree).

However, drive around Brisbane and other subtropical towns in Queensland, and the chances are you will see this tree flowering brightly. Due to climate change, it is also now found growing further south.

A spokesperson from Biosecurity Queensland said State and Territory governments each have their own process for listing plants under their biosecurity or noxious weed laws. They are currently working with the Australian Government to harmonise biosecurity arrangements due to increasing public sensitivity to the impacts exotic plants have on the functioning of natural ecosystems.

Stingless Bees Under Threat

The African Tulip tree is of particular concern to beekeepers like Bob Luttrell, better known as Bob the Beeman, as it conceals a lethal threat to our stingless bees. Bob’s website provides useful material to those likely to come across stingless bees in their work of removing or working with trees, in the hope that in some way the information will help comprised colonies to survive.

Bob said stingless bees are very much attracted to the sprays of African Tulip flowers.

“Look closer and you will see the bees gathering pollen, and seemingly imbibing other plant secretions as well as nectar.

“Unfortunately, if you continue the examination into the flowers, you will find the result of that foraging for pollen and nectar – a collection of dead and dying stingless bees and other insects.”

He said studies in Brazil, where the tree is also a problem, found that the gathered pollen did not get back to the hives. So the attracted bees are killed before they can return.

“Unfortunately the mechanism of attraction is strong and the numbers of stingless bees can be quite large in areas where stingless bees are present,” Bob said.

“I know of no other tree that flowers for such a long period, many months through the winter period, and most of the year in the tropics. That alone sets it in a league of its own. It is an attractive food source for the bees, at a time when there is not a lot of choice. The bees that are killed are the most experienced foragers, the scout bees, that look for sources of food for the colony. Because they do not get back to the colony, no warning can be developed, so the loss of bees will continue.”

Bob said the public has become more enlightened about the importance of taking care of our native bee populations, and that is providing motivation to remove weed trees such as the African Tulip.

The Gold Coast City Council recently took the educational aspect one step further by assisting a community initiative to help Australia’s native bees. It has set aside $30,000 of funds from its ‘Our Natural City’ strategy to subsidise the purchase of native bee hives city-wide. Property owners on 1200 + square metres will be eligible for $250 to go towards their hive purchase. A typical bee hive only requires maintenance every 12-18 months and the Council also runs Stingless Bee Keeping workshops.

For more information see http://

Did you know?

Did you know that in its natural environment in Africa, Spathodea campanulata can survive between 50 to 150 years and has many uses: light brown wood is used for manufacture of paper, drums and carving; bark is used in treatment of rashes on the skin of newly born babies, as a laxative, and an antiseptic to prevent growth and development of microorganisms; open boat-shaped pods are used as children’s toys due to their floating ability; and the trees also provide shade in coffee plantations and also as live fences.


“Insect Mortality in Spathodea campanulata” BEAUV. (BIGNONIACEAE) Flowers by Trigo. J. R. and Santos, W. F. dos Rev. Brasil. Biol., 60(3):537_538.

October 19, 2019 / by / in , ,
Work Athletes

At Citywide, we take an holistic approach to arboriculture that ensures all our staff take care of themselves and their teammates.

Whether it involves climbing and rigging, using one of our specialised elevated work platforms (EWPs) or constantly feeding wood chippers with heavy, cumbersome logs, the importance of maintaining good health and fitness through proper nutrition and staying well hydrated is paramount.

Observe a climber who is hungry or thirsty and wants to get out of the tree. The timber he or she cuts grows bigger and more unwieldly. They won’t climb as high and they refuse to limb walk. Decision-making gets worse, frustration builds and an incident occurs.

As Arborists and Ground Crew, we work long hours often in extreme temperatures, doing heavy manual labour and often in awkward positions. We climb out on long branches and contort ourselves into weird positions, wielding heavy chainsaws at weird angles, always striving to get a perfect cut.

We spur-climb with a heavy chainsaw hanging from our harness. We flex every abdominal muscle while holding the tools of our trade to ‘block down’ large timbers. And we drag heavy branches through narrow areas, to a chipper truck that always seems to move further away each time.

Indeed, the life and work of an arborist is akin to being a high performance athlete. A ‘work athlete’.

So, just as hydration and nutrition are key elements to an athlete’s wellbeing and ultimately helping keep them on track, so too do we ensure our people are in the best possible physical and mental shape.

It’s a duty of care that’s in our DNA and central to our mission and purpose of safely shaping liveable cities.

For more information about our company and values visit or send an email to [email protected]

October 17, 2019 / by / in , ,
Ingenious Solutions

So you have issues with access? Or perhaps the tree isn’t safe to climb? Fear not, Global Machinery Sales has a suitable solution for your problems.

Introduced into the Australian market by Global Machinery Sales in 2012, CMC Lifts Australia offers a range of compact and highly manoeuvrable spider lifts as well as heavy duty spider lifts with big height and reach.

Global Machinery Sales Director Brian Evans has worked diligently with top EWP dealers in the USA and Europe to bring you a world renowned leader. “We wanted to pick the world’s best brand once and not have to pivot between brands and suppliers, by finally bringing superior quality and value to the EWP market in Australia. After speaking to CMC dealers who have sold alternative brands in the past, we found how happy they are and how superior the CMC product is compared to other brands. CMC seemed the obvious choice,” Brian said.

The dealer in the USA sells 150-200 CMC lifts per year, stating it was the best decision he ever made, minimal warranty issues, great support and a very well built machine.

Today CMC Aerial Platforms are a world leader in aerial lift technology and are a best seller in 30 countries worldwide, integrating ingenious new ideas and always building lifts “with the operator in mind” translating into an easier to operate and less extensive aerial lift. This winning combination gives Global Machinery Sales’ customers better value and a greater ROI.


The CMC S19HD is a track mounted spider style mobile elevated work platform and it has been designed with your job in mind. “The tree industry is tough and any steps we can take to make it easier and safer are welcome, which is where the CMC S19HD comes in. It’s here to do exactly that,” Brian added.

“Impressive side reach, so stable and secure!” – this is the first reaction and comment from everyone that takes a ride on the heavy duty S19 Spider Lift.

It features an extremely compact stabilisation area with full side reach, including the ability to self-level on steep sloped floors and terrain.

In addition, the S19HD is also capable of setting up in “narrow mode”, with an even smaller footprint. This special feature means reduced outreach, however the lift is still capable of full 360° rotation and full vertical height. Designed and built with a configuration of one lower riser pantograph and two-telescopic boom extensions, the S19HD has a 200kg basket capacity and 180° basket rotation, with close to 19m of working height.

Compact dimensions of 0.95m W x 2.04m H means access to virtually any work area.

CMC S25 Spider Lift

If the S19HD doesn’t fit your height requirements no need to worry, the CMC S25 tracked spider lift will fit your needs perfectly. This reliable 25m working height lift has an impressive 14m outreach.

The S25 is a self-propelled tracked aerial platform, designed with 1 articulating/1 telescopic lower boom and 1 articulating/2 telescopic upper booms, plus an articulating jib on the end. This combination allows for best work manoeuvrability and outreach.

A quick release 180° rotating basket with triple safety locks rounds out this great lift that is a pleasure to work with. Standard basket size is 1.70m wide. Other smaller basket sizes are also available to best fit your application.

The S25 comes equipped standard with two stabilisation areas and six possible outrigger configurations. With incredibly compact dimensions of 1.01m x 2.045m x 6.05m (WxHxL), in the closed travel position, this serious aerial work platform is capable of entering virtually any door. Quiet diesel engine/240v electric hydraulic power pack is standard. Also available with hybrid power source. The CMC S25 takes the place of the best-seller S24, improving its performance and reliability.

For more information please call Global Machinery Sales on 1300 072 926

Pay a visit

October 15, 2019 / by / in , ,
Stationary Rope Technique Systems

An introduction to Stationary Rope Technique (SRT).

Vermeer Australia and Joe Harris, along with some of Australia’s most renowned climbers, have joined forces again to deliver the annual Vermeer Arborist Seminar Series for 2019. This year, the seminars focus on a topic that has become a talking point in recent years: Stationary Rope Technique (or ‘SRT’, formerly known as Single Rope Technique). The 2019 series provides the opportunity to learn about SRT and try out some of the different SRT systems available today.

We spoke with Joe Harris, internationally recognised trainer and tree climbing champion, who touched on the key elements of SRT as it relates to climbing arborists.

What is Stationary Rope Technique?

“Stationary Rope Technique (SRT) is a method of ascending, work positioning and descending from trees using an assembly of configured arborist climbing equipment such as ascenders, descenders or dedicated SRT work positioning systems.

When using SRT, climbers move up and down along a climbing rope – whilst the rope itself stays in the same place (stationary). In traditional climbing systems, the rope moves back and forth over the high point as the climber ascends or descends. This used to be called Doubled Rope Technique or DdRT, and is now called Moving Rope Technique (MRT).”

Benefits of Stationary Rope Technique

  • There is consistent friction at the hitch regardless of the number of redirects – therefore it is easy to achieve good rope angles and set multiple redirects
  • This technique may not require isolation of the tie-in-point, so it is quick to set in some configurations
  • With SRT, the use of ascenders or similar SRT equipment can make long ascents very efficient and fast
  • Only a single rope length reaching the ground is required
  • A wide range of equipment exists for ascending, descending and work positioning on stationary rope, and equipment can be configured into a number of different systems
  • SRT climbing systems can be used to perform almost any tree climbing task
  • The installation of multiple natural redirects has no impact on the climber’s ability to control the friction in the climbing system.

NOTE: It is very important to ensure that you understand the full range of functions of any SRT device, as well as the correct configuration and any possible risks or misconfiguration, before leaving the ground.

Presenter Bio Joe Harris, Cert. Arborist / Contract Climber

Joe is an internationally recognised trainer in Advanced Rigging and Forces, Advanced Tree Climbing and Aerial Rescue, and has presented at Arboriculture Australia and ITCC events.

In addition to presenting the Vermeer Arborist Seminar Series, he has presented workshops in Belgium, France, Germany and the US, and produced instructional videos for ART.

His achievements include being a two-time Australian tree climbing champion, silver medalist at the International Tree Climbing Championships, and an array of national achievements.

“Broadly speaking, the differences between SRT and MRT result in a different way of planning work within the tree. MRT climbers are said to see the tree in rows – planning to go out and back on each branch that is to be worked on. SRT climbers tend more toward working in columns – going up and down the rope with less lateral movement.”

The Vermeer Arborist Seminar Series kicks off again between August 9 and 31 in Brisbane, Melbourne, Sydney and Adelaide. This year’s one-day format offers a morning theory session followed by an afternoon practical climbing session to put these new techniques into practice. This year, attendees will leave the event knowing what SRT is and why they should use it, how to assemble safe and efficient climbing systems for ascent and work positioning, smooth climbing techniques with SRT systems, how to get the most advantage without any of the disadvantages, and tree work strategies to get the most benefit from their SRT climbing system.

In the interim, if you are interested in trying out any SRT ascenders, descenders or other devices, you can trybefore-you-buy in the Climbing Zone at your local Vermeer Parts Counter.

Call 1300 VERMEER or visit learn more about our arborist gear and dealership locations.

October 13, 2019 / by / in ,
Light And Powerful Husqvarna’s New T525

Husqvarna’s new T525 – making light work of all your trimming jobs.

Husqvarna introduces a new petrol top handle chainsaw for arborists, one of the lightest on the market.

Like every other chainsaw Husqvarna makes, the T525 has powerful performance that professional users appreciate, but perhaps the greatest advantage is the level of engine performance packed into a lower weight saw. This means improved productivity, since power and performance are not sacrificed for a lighter product, and users can cut with less strain on the body, another important benefit for tree care professionals.

With quick acceleration built-in and Husqvarna’s signature X-Torq® engine, ensuring higher power output compared to other tree care saws, the T525 is designed for tree care professionals who want maximum productivity with minimum downtime. X-Torq® also means improved fuel efficiency and lower levels of exhaust emissions.

Features for working in the tree

Reliability is another important factor for tree care specialists, particularly when working high up in a tree. A durable and easy-to-access belt eyelet allows the saw to be quickly connected to and disconnected from a climbing harness. A side-mounted chain adjuster with retained bar nut allows professionals to easily adjust and tension the chain while up in the tree. The spring-assisted start allows for lower pull force, meaning less effort is required to start the engine, and the auto return stop switch means the saw is always ready to start.

The Husqvarna T525 is available to purchase from your local Authorised Husqvarna Dealer.

For more information visit

October 10, 2019 / by / in , , , ,
Monitor Lifts Range

In the arborist industry, working with mobile equipment and specialised height access solutions can significantly reduce risks associated with climbing as well as dramatically extend the careers of individuals whose bodies aren’t up for climbing anymore.

Buying the right machine is a huge decision. Pricing, features, versatility and after-sales service and access to spare parts all need to be factored into the equation of what is real value before committing to a purchase.

Monitor Lifts not only offers an impressive range of lift styles and sizes, but also has a remarkable and dedicated Australia-wide service and parts network. With dedicated parts and personnel and factory-trained technicians in every state along with a number of regional partners, Monitor understands the importance and significance of this level of customer service.

Monitor itself is a great Australian success story, with Colin being the father and founding partner with his older son Tim, and then youngest son Ben joined the team a little later.

The products themselves are top quality European-made machines, which have been reaching great heights here in the Australian Market. Their range includes the very popular Spider Boom Lifts which have been widely adopted into the Australian industry. Due to their super compact designs, these models are the first choice where access is very limited. The initial offering from Monitor began when they started importing the Leguan Spider Lifts from Finland over 20 years ago in 1997. The Leguan Spider Lift offered unparalleled stability and support even in uneven terrain.

The next addition to the Monitor Lifts range came in 2003 when the OMME spider lifts were introduced. Since then, the OMME range has been significantly suited to a variety of civil engineering, construction, maintenance and arborist work throughout Australia. Consisting of the 1800RXJ, 2350R, 2750R, 2750RX, 3150R, 3710R and 4200R, the OMME Spider Lifts have an extremely versatile range of capabilities.

It was in 2005 that Monitor discovered the very impressive Platform Basket Spider Lift in Italy. The innovative designs struck a chord with end users in Australia and New Zealand, and today there are more PB Spider Lifts in Australia and New Zealand than any other brand. These spider lifts are now the benchmarks in each category in the industry.

It’s a combination of the amazingly narrow and compact design, yet substantial power and performance that has separated these spider lifts from the crowd. Ranging from the PB1380 Spider Lift through to the PB3315, this impressive line-up is a top choice for rental companies and arborists. The user-friendly, intuitive controls that offer smooth boom operation and drive functions all combine to the impressive handling of the range.

When we here at AA heard that General Manager Ben Joyce was going to be in the Sydney office/warehouse out at Seven Hills, we arranged to pay a visit, which Ben was thrilled about.

The new warehouse facility was well organised, very tidy and had many machines prepared and ready for deliveries across Australia. So, there are bound to be some delighted customers receiving these impressive new machines in the next week or so. With many machines and spare parts on site, I was intrigued by a Rail Boom Lift which has been designed as a dedicated road and rail boom lift. Known as the RR14 Evo, its specs considerably outperforms traditional modified products with a host of railway dedicated features. A few specific features that jumped out to me was the fact that this hasn’t just been modified for rail use but designed from the ground up, which significantly increases its operational speed and performance. The self-levelling turret provides excellent stability. These machines are also certified to drive and work on a 200mm cant (8-degree side slope). As well as sporting an auxiliary diesel engine for emergency recovery, the features and benefits of this range truly set it apart from the crowd.

When chatting with Ben, it was great to hear the passion and pride in which he spoke about his range of machines and how hard Monitor had been working to ensure the best possible experience for their customers from an after sales, service and spare parts perspective. When asking Ben about the lengths they have gone to, to keep this side of the business so successful, he shared: “Superior training and support for both our national staff and customers is something that we have dedicated ourselves to.

We have created user-friendly operator training packages for all our models, including familiarisation videos on each machine. Customers just need to scan the QR codes for the machines, then watch and learn. As well as this, we provide national service training classes regularly throughout the country, which are available to every Monitor Lifts owner.”

Ben continued, “Last but by no means least is our 24/7 Support Program, where customers can call our 1800 025 024 number day or night, and a dedicated Monitor technician will be in contact with the customer to provide fast advice and support.” It’s this level of support that sees customers coming back for their second and third purchases when the time and occasion is right.

Something that Ben shared that made an impression with me was the fact that as these quality machines are European made, and the sourcing of spare parts from Europe can take weeks or months, Monitor keeps more than 1 million dollars’ worth of spare parts in stock in Australia – allowing Monitor to achieve a 92 per cent spare parts fill rate. The accountant isn’t too happy about having $1 million in stock sitting in a warehouse, but it’s this fact which sees customers Australia-wide receiving their required parts or components in a matter of days or even overnight, depending on the size of the item, and being able to have their equipment up and running as soon as possible.

Call 1800 025 024

For more information visit

October 8, 2019 / by / in ,
Grand-Border Stressed/Dying Pines

Non-sustainable vegetation management – modern horticultural practice – an industry-driven tree killer?

My apologies to AA readers for holding back on Part 2 of ‘Conservation Arboriculture in Action’. Part 2 is based on a recent Treepeeps PTY LTD advanced tree – tree planting project. At the time of drafting Part 1 (last edition), I had expected for us to have completed the job soon enough to write the Part 2 article. Not so, in the meantime I am sharing this article on tree decline based on non-sustainable land management.

This article is founded on a report I drafted for a S.E. Queensland council. As a professional arborist I have worked contractually and as a consultant all over the world, Australia, PNG, Vanuatu, America, Canada, Germany, Portugal and the United Kingdom. As a traveller I have also explored much of Europe.

All round the world I have seen the same standard of a collective lack of tree care, with most amenity trees seldom living beyond the first 1/3 of their lifespans.

This is because of environmentally non sustainable land management practices – largely driven by horticulture, with nonsustainable development, agriculture and arboriculture driving home the final coffin nails. Few of us have the awareness or the gumption to speak out, let alone the fortitude to make change.

Even in our profession we have enabled industry to direct our cultural practises to do more damage to trees than benefit them, our limited education (i.e. a lack of biology) is also a reflection of an industry drive.

To achieve sustainability enterprise must balance the environment with economy, there can be no shortcut. The model that is current to land based industry around the world is failing.

The following report is a reflection of the kind of horticulture that kills trees Australia wide.

Project – Mossman Park, Stevens Oval and D’Aguilar Highway, Dalby and Jondaryan S.E. QLD.

Following a request from the VACC Parks and Gardens Coordinator – to assess three treed avenues at Mossman Park, Stevens Oval (Dalby) and D’Aguilar Highway (Jondaryan) – I carried out site/ tree assessments on 18/12/18. The scope of the assessment was to ascertain stress factors (on top of drought stress) likely to be causing tree decline and death. With the three sites in mind approximately ¼ of the Pine trees are dead with more dying.

Status Report

The first site assessed was the avenue of trees on Domingo road adjacent to Mossman Park. The trees are a mix of Pinus spp (Pinus radiata or possibly Pinus taeda), Hoop pines (Araucaria cunninghamiana) and Kauri pines (Agathis robusta), though largely Pinus (as requested this report is concerned with the Pinus spp). Though there has been a recent history of drought there had been rainfall before my arrival on site and the soil was well hydrated.

The Pines stand at (on average) 15m tall with an approximate crown spread of 3-5m. The stem diameters (at chest height) average 40cm and the trunk flare diameters (at ground level) are around 60cm. These trees are largely made up of a single main stems, have symmetrical crowns (trunk, branches and canopy) and are approximately aged 30+ years. The Mossman park avenue is made up of approximately 50 trees.

A question has been raised in relation to the trees condition with the long term in mind, the symptoms that bought these trees into consideration involve scattered dieback in the internal foliage of the trees, leading to complete folial/canopy/upper crown death. Study of the Hoop pines and Kauri pines shows that these trees are also showing stress symptoms.

Evidence of Genus, Species and Health

The Pines – (P. radiata or P. taeda) have fair/poor vitality to none – this is evidenced by stunted foliage, leaf size and leaf colour, leading to death evidenced by scattered dieback in the internal foliage of the trees, leading to complete folial/canopy/upper crown death.

Evidence of Crown Structure (relating to biomechanical assessment)

The crown structure of these young trees is fairly standard for the Genera (Pinus, Araucaria and Kauri) which is generally stable even when stressed in my experience of S.E. QLD. Though the focus of this report relates to tree health.

Observations/Discussion – Site Limitations/Herbicide Concerns

The first study site is where I spent the bulk of my time (my observations of that site form the backbone of this report), study of the second two tree avenue sites validated my observations of the Domingo road avenue. Study of the trees in general revealed that the Pine trees are the most sensitive of the avenue trees to the environmental conditions. Though the other tree Genera reveal symptoms that support the decline in the Pines.

The three avenue sites (ref: Fig. 4. and opening image on page 32, Mossman Park, Fig. 6. Stevens Oval, Fig. 7. D’Aguilar Highway) share identical features/symptoms.

  • The trees are roadside with the bulk of their root systems being in adjacent gullies
  • The growing environments are regularly mown lawns
  • All trees have recent evidence of herbicide application within their structural root zones
  • The avenue trees are surrounded by old agricultural land • The soils are heavily compacted (years of transport vehicle, mower and people access)
  • Crown dieback largely in the Pine trees (ref. Figs 2-7.), but also noted in the Hoop pines (ref. Figs 16-21)
  • Most of the trees have mower damaged exposed roots (ref. selection of Figs 8-12)
  • Large swathes of dead lawn was noted, mostly in gully areas between/adjacent to trees (ref. Figs 13-15).

As well as the major symptoms listed above this report details my other observations and reasoning as to why the VACC Pine trees are in decline.

The avenue sites are by their nature problematic as growing conditions for any tree. The soil compaction and lack of nutrient cycling through the soil profile is known to have a significant impact on tree longevity in itself.

But the sustained use of herbicide application and mower damage on structural roots must be considered, mower injuries are similar (on the impact to trees) as perennial cankers in that as soon as tissue is generated by the tree to close the wound it is damaged on the next round of mowing (the same pattern occurs with canker infection or bird damage).

The wound wood being generated by the tree starts of as cambial tissue which may absorb a measure of the herbicide itself, though it is understood that this usually only occurs with the presence of chlorophyll in plant tissue (perhaps not always present in cambial tissue in stems or roots).

Based on my studies and the evolution of Plant Health Care science (ref: Soil Food Web principles – Dr. Elaine Ingham) the key issue that sustained herbicide use has on soils relates to excess salt.

Bituminous road surfaces are know to leach chemical salts (pollutant runoff is also a factor) that impact on soil health. Trees as woody plants need oxygen and microbial association in soils for sustained nutrient exchange, prolonged lawn environments are known to lead to depletion in essential soil microbiology for woody trees. Though the build up of salts and heavy metals are also a key issue with tree health. Figs. 13-15 are indicative of issues below ground with impacts on turf as well as the trees.

Further to my observations of the trees I make reference to observations of the Hoop Pines (ref. Figs. 16 to 21). Study of the Hoop Pines in all three sites revealed symptoms/perceived stressors that need to be discussed. These involved dieback in shooting epicormic growth (mostly shoots generated following lower branch removal ref: Fig. 16) as well as internal dieback (similar to that of the Pines ref: Fig. 18), comparison to other local Hoop pines in surrounding areas showed me trees without these symptoms. I suspect that this is another indicator of site issues below ground, though I believe that management need to carefully consider herbicide application as being a direct impact.

Discussion with fellow consulting Arborists via the Facebook Australian Arborists Network AAN – Brands such as Roundup, Grazon, Conquest, and chemicals Glyphosate, Picloram, Triclopyr, Metsulfuron-methyl, Dicamba have all been cited as having a direct influence on tree poisoning and death.

It has also been discussed within my circles that Hoop pine deaths are attributed to herbicide application.

Pine nematode Another possible factor in the trees decline which requires consideration and elimination is Pine nematode – Bursaphelenchus vallesianus. Outbreaks of Pine Nematode have been recorded in the Sydney region (2016) and are discussed in this document (since publication the nematode has spread north and is now reputed to be in northern NSW State Forest). Check out: plant/insect-pests-and-plant-diseases/ pine-nematodes? fbclid=IwAR1N6O8TK RIS5S3DjaX-ZgDjyhsANxZQO3E6cRUfkpsRJDPB0k1DGEshDk

Study of the above does provide similarities to the dieback symptoms discussed in this report. The nematode impacts on the trees vascular system by forming air pockets which causes death.

The Pine nematode has been discussed as being present on the following Pines:

  • Aleppo pine (Pinus halepensis)
  • Austrian pine (Pinus nigra)
  • Common spruce (Picea abies)
  • Maritime pine (Pinus pinaster)
  • Ponderosa pine (Pinus ponderosa)
  • Radiata pine (Pinus radiata)
  • Stone pine (Pinus pinea)
  • Scots pine (Pinus sylvestris)
  • Turkish pine (Pinus brutia)

The contacts concerning this matter I made where via the Department Of Primary Industries – DPI NSW and the Department of Agriculture and Fisheries – QLD who I have alerted to the possible issue of a Pine nematode outbreak, at the time of my completion of this report DAF staff where due to make contact.

For a useful conclusion to be reached there is the need for further investigation, I recommend analysis of the soils for salt and heavy metal levels, I also recommend that Council compile a list of all products that are currently being used for herbicide application (as well as frequency of application) as a means to assess/ eliminate the contributing cause of the tree decline/death. Bearing in mind that the herbicide companies downplay the side effects of the products they sell I am more inclined to pay attention to field experience than the ‘literature’ on this topic.

For Analytical services we recommend Southern Cross University Lismore to assess the sites soils for heavy metals and salts—eal/

Concerning the possible outbreak of Pine nematode for the record – all pests and diseases are side effects of site issues that impact on tree health, in the case of trees – site issues impact soils which impact tree vitality (principally a lack of soil oxygen, humus for nutrient cycling and allied micro-organisms that compartmentalise disease causing organisms in the soil). Study of the linked Pine nematode document validates this by stating “Control of pine nematode is limited to prevention”. If the Pine nematode is present this will have to be accounted for but not at the expense of treating the site constraints and the factors that have lead to the cause of the most current problem (note – contact with DPI NSW Biosecurity validated my observation that the Pine nematode is an issue only on stressed trees).

Road side avenues of trees are probably the most sensitive and vulnerable to health limitations, tree death is almost always a result of multiple imposition, good management involves removing or reducing stress factors that impact on trees. Non-sustainable horticultural practices are in my opinion the key constraint that require management input.

As a matter of short term and long term soil/tree health I recommend improving on the avenue trees growing environments by establishing Nutrient Beds (comprised of cold processed composted mulch). To help keep people off the Nutrient Bed and accelerate the assimilation of nutrients (activate the soil root-interface) I also recommend the establishment of a Plant System (plant component of an ecosystem), to help proof the nutrient bed and keep vehicles out (exclusion zone). In the course of establishing a plant system I also recommend vertical inoculation of the trees root zone with Soil Food Web grade cold processed compost – humus (this can be done at the time of planting tube stock vegetation).

Trees which have died are best replaced by Hoop pines which are considerably more tolerant of the site constraints.

The use of herbicide in the trees root zones is a practise that needs to be replaced by a more sustainable means.

Likewise to enable wound wood generation and compartmentalisation of exposed sapwood from root damage and likely inoculation by herbicide – lawn mowers need to be kept out of the tree root zones.

If it is not feasible to establish nutrient beds and plant systems I recommend the planting of rings of sturdy vegetation – such as Lomandra hystrix around the structural root zones of trees (as a minimum) to keep mowers/spray crews out. Grass can be cut to the edge of these plants which even deflect brush cutters. The solution to non-sustainable horticulture is sustainable horticulture, practised by old school horticulturists around the world.


In conclusion with thanks to VACC senior management being responsive to recent rapid tree decline this report is a reflection of symptoms presented by the site and the resident avenue trees.

Following rapid death of Pine trees located within three avenue treed sites in the Grand-Border region at Dalby (*2 sites) and Jondaryan (*1), on behalf of VACC I was commissioned to assess the trees with a view to determining reasons for decline in association with drought.

Modern Arboriculture recognises that tree decline/death is generally caused by multiple factors working against the tree as one.

My 18/12/18 assessment has validated this understanding, the combination of soil compaction, lack of nutrition, drought, mower damage, excess herbicide use, the build-up of salt (in the soil profile) and heavy metals, has lead to excessive stress loading on the Pine trees which are the most sensitive to these site limitations. Arboricultural experience supports the symptoms of rapid tree death to herbicide use (this report has recommended that VACC do an audit on brands/types of herbicide used, as well as frequency of application). Likewise the study of information residual to the symptoms  presented by the trees has revealed that there is a recent outbreak of Pine nematode extending North from Sydney, out of responsibility I notified DAF of the issue and an investigation by the department is now underway (advice relating to the management of Pine nematode is available within the document linked on page 36, Observations/ discussion/Pine nematode).

With prevention of such declines I have recommended the review of horticultural practises, as well as cultural improvement of the sites soils, this is with a view to protecting the Hoop pine population which are more resistant to the issues behind the Pine trees decline and death, I have also recommended replacing the dying Pines with Hoop Pines for this reason. If the sites in question do prove to be infected with Pine nematode a protocol has been established by the DPI for its management, this will need to be considered in relation to advise from DAF.

Post-report conclusion For the sake of this technical feature, I have altered names locations and dates in the report, the photographs and content of the report remain true.

Following the drafting of this report DAF made contact with me to confirm that there was no Pine nematode – Bursaphelenchus vallesianus present in any of the soil profiles they sampled concerning the 3 sites (this report I passed on to the client along with my contacts). When we consider the long term economic and environmental costs of managing trees non-sustainably verses via sustainable systems (post establishment) the benefits are multifaceted. The problem is getting tree and people managers to start. To create the precedent for conservation arboriculture we need good local government support, a challenge when we live in a society that makes an economy from being non-sustainable, such as via repetitious herbicide use.

With sustainable tree management in mind Conservation Arboriculture is the solution, though this will save money as opposed to make money – perhaps an anathema to industry, but a great boon to land/vegetation managers. The enterprise of such management and CA will get arborists out of trees and into the soil…

Long live the rhizosphere.

October 6, 2019 / by / in , , , ,
Going Places

Being an arborist has its challenges, one of the biggest being able to access areas hard to reach, with small and narrow entrances.

After the tree has gone, perhaps due to disease, safety or simply being in the wrong place – the stump remains and access with a grinder is required.

With many arborists offering stump grinding as a service, it’s essential to be able to tackle jobs that arise, that’s why Thor’s Trees purchased two Predator 360 stump grinders.

At under 660mm wide, Thor’s Trees can service with ease, especially houses that are shoulder to shoulder and have difficult access.

“It has a great swing for such a compact grinder, at 812mm or sixty degrees, it’s unmatched by any other stump grinder on the market.”

The Predator 360 boasts a cutting depth of 355mm and a weight of only 145kg, meaning this machine is going places. In addition, with its fold-over handle, lifting eyes and handles to the front and rear, you can transport it in practically any truck, ute or trailer.

Its central pivot turns a job that should be hard work into something that can be repeated over and over again without tiring the operator.

Lawrence Thor, Managing Director of Thor’s Trees said, “I chose Predator as they’re the best on the market, they have a great reputation and their customer service (through Hansa Products – the local distributor) is excellent.

Lawrence mentioned that the investment was a great choice with a quick ROI compared to hiring one.

“In terms of ROI we managed to pay off the Predator 360 stump grinder in three months thanks to the accessibility to many jobs it enables.

The manoeuvrable, well built, efficient, powerful machine with a US patented multi-tip cutting system as standard is approximately 30 percent more efficient than the same machine with finger teeth and local schools.

The Predator 360 is the smallest pedestrian grinder available through local distributors Hansa Products. With small handheld grinder attachments, pedestrian models, as well as larger remote-controlled models up to 65hp on offer, there is bound to be a Predator suitable for every stump that need grinding.

Hansa Products are the sole distributor of Predator Grinders in Australia and New Zealand.

For more information visit

October 2, 2019 / by / in , ,
Little Helper

Hacksaw won’t access that metal pipe? What’s the solution?

You can either take out the blade, wrap a roll of duct tape around it to make a handle and watch it bend or break as you push on it or you can take the metal cutting Silky Mini Mini from the toolbox and get the job done quickly and easily.

The Silky Mini Mini from Japan is small and easy to manoeuvre into tight places, but has the cutting ability of a full-size hacksaw and stays sharp four times longer.

These little beauties cut in both directions, on the pull stroke as well as the push stroke. They are so compact that take up practically no room at all.

The blades are only 160mm long and are made from top-quality steel, strong and flexible. They have the handles that absorb vibrations and come with a protective cover for the blade. No cutting the fingers as you dig through the tool-box to find it.

Another praised feature of Silky Saws in Australia is that replacement parts are available for all saws. Lose the screw, just order a new one! All parts are in stock in the Brisbane warehouse.

You also have the choice of two other blades that will fit on the Mini Mini handle: one designed for cutting plastic (great for conduit) and the other designed for hobbyists working with wood.

Silky Mini Mini is the right choice for a huge range of applications, with a very small price tag.

Call Arborlab Tree Care and chat with Jannita on (07) 3823 1599

View them today at

October 1, 2019 / by / in , , ,