· the right tree · in the right place ·
· for the right reason ·

TREAT News | Dry Season July - September 2019

Annual General Meeting

TREAT's 37th Annual General Meeting will be held on Friday 6th September at the Yungaburra Community Hall commencing at 7.30pm. The presentation of annual reports by the President, Treasurer and Nursery Manager will be followed by the election of TREAT office bearers for the next year. Nominations are invited for the various positions on the TREAT management committee and will be accepted until 22nd August. A list of nominees will be available for viewing at the nursery by members for 2 weeks prior to the AGM. Members are reminded that they must be financial when voting for the new committee. Subscriptions will be accepted at the AGM. A General Meeting follows the AGM.

Our guest speaker for the evening will be John Clarkson who will be known to many of us. He is a Principal Botanist with QPWS based in Atherton and has over 40 years of experience in flora survey and mapping across northern Australia, particularly on Cape York Peninsula. His talk 'What's in a Name' will explain how names are applied to plants and the rules that govern this, and the importance of using plant names correctly. He will also try to demystify why it is sometimes necessary to change names with which we are familiar, and show the confusion that can be caused by using common names. John will give some practical examples of naming plants based on his work with the genus Erythroxylum.

After Q and A time following John's talk, the evening concludes with a supper. Plate contributions are appreciated. Everyone is welcome to attend.

Inside this issue

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Can Biodiversity Plantings Earn Income as Carbon Farms?

Cath Moran, Dave Hudson, Dave Skelton

Planting trees removes carbon and helps to manage climate change

The release of greenhouse gases by humans has destabilised the global climate, causing ongoing climate change. Carbon dioxide is released from burning fossil fuels and is the main greenhouse gas released by human activities. In addition to the obvious need to reduce the amount of carbon we release into the atmosphere, removing existing carbon from the atmosphere is also an important way to limit the amount of climate change we face. Planted seedlings absorb carbon dioxide gas from the atmosphere during photosynthesis, then store much of the carbon in their stems, trunks, leaves and roots. This is a form of what's known as carbon sequestration.

The Federal Government set up the Australian carbon farming program in an effort to reduce the amount of greenhouse gases released from things like farming livestock, controlled burning and landfill and to encourage carbon sequestration through actions such as tree planting. The carbon sequestration part of the program provides incentives for absorbing carbon and offers carbon credits - essentially certificates that can be sold for money - for every tonne of carbon sequestered over a 25 year period. Carbon credits can be sold to organisations who need them in order to release the equivalent amount of carbon through their operations; in this way, the carbon released by one activity is balanced (or offset) by the carbon absorbed in the carbon farming project. This is a key part of Australia's attempt to meet our international commitments to reduce our carbon emissions and the Federal Government takes out 'abatement contracts' to buy carbon credits earned by large sequestration projects. Carbon credits can also be sold directly to organisations who voluntarily want to become carbon neutral or to pay for the climate benefits of carbon sequestration, for example if they see it as part of their corporate responsibility.

Model: Larry Crook, Photo Campbell Clarke

Planting trees absorbs carbon from the atmosphere, helping to manage climate change, and it also makes people happy. Model: Larry Crook, Photo Campbell Clarke

Of course, planting trees can also have important environmental benefits like increasing habitat for biodiversity, stabilising soil and protecting water quality, as well as social and cultural benefits. From the carbon farming perspective, these are known as 'co-benefits', because while they are additional benefits of tree planting, they aren't the primary motivation for the carbon planting. For many people involved in TREAT, improving biodiversity value is the main motivation for planting and the situation is reversed - in biodiversity plantings, the carbon sequestration value is a co-benefit. At the moment, the biodiversity value of plantings isn't monetised, but thanks to the carbon farming program, the carbon sequestration co-benefit has economic value as an ecosystem service to society. However, if biodiversity plantings aren't registered as carbon farms, they don't earn money for providing this service.

Earning an economic return on plantings won't contribute to their biodiversity value, but it's clear that we need to plant many more areas of land in our region. More habitat is needed to maintain plants and animals that have suffered from extensive clearing, and we need to restore forest in areas with suitable climate conditions that will support Wet Tropics species in the future. Part of the reason more areas aren't revegetated for biodiversity is that the land can be used to earn income from other uses, like grazing or cropping. The cost of establishing and maintaining a biodiversity planting can also be a barrier. It follows that if money could be earned from tree planting, more land could be planted for biodiversity. Could the carbon farming program present an opportunity to increase the scale of tree planting in the Wet Tropics, with benefits for both our climate and biodiversity?

revegetation site

We need to scale up the area of land that's being replanted it we're going to restore enough habitat for Wet Tropics plants and animals to persist after clearing and in hte face of climate change. This could be more likely if the costs of planting trees are offset and if tree planting is an economically viable alternative to other land uses.

Could biodiversity plantings earn money as carbon farms?

The short answer is that yes, biodiversity plantings can earn money as carbon farms. The basic criteria for carbon sequestration plantings are that projects have to:

Biodiversity plantings meet these criteria, and easily exceed the height and canopy cover requirements.

However, on top of the costs of planting and maintaining a planting, there are costs involved in registering a planting as a carbon farming project. So, the practical question is whether or not these costs could be offset by the carbon credits they earn?

Certainly, carbon farming by tree planting is a viable economic option and commercial carbon farming tree plantings have been established in Australia, though they typically use relatively low-cost planting methods compared with our biodiversity planting model. For biodiversity plantings to be profitable, the amount earned would have to be fairly high to offset the costs of planting (let's say around $33,000 per hectare). This would be possible if:

  1. the method used to measure the amount of carbon sequestered in a planting calculated high sequestration from biodiversity plantings, which therefore earned a lot of carbon credits;
  2. the price for carbon credits was high; and/or
  3. the additional biodiversity values of biodiversity plantings attracted a higher price.

In order to find out whether or not biodiversity plantings could generate income as carbon farms, Terrain NRM supported TREAT to run a pilot project on the ground, going through all the steps required to set up and run a carbon farming project, to keep track of the skills and time required, the costs and the economic outcomes under different scenarios.

The 'Freemans Forest' carbon farming pilot project

Most people will be familiar with the block known as Freemans Forest Nature Refuge, adjoining Lake Eacham National Park, that was bequeathed to the South Endeavour Trust Pty. Ltd. by the late Ian Freeman and which has been progressively revegetated since 2011.

In 2017 TREAT registered a carbon farming project over a 1.6 hectare area of the Freemans Forest property where a new planting was planned. Registration has to happen before planting is done and involves designing the planting project, working out which of the program's approved methodologies is appropriate for the project, gathering supporting documentation, GIS mapping, and estimating the amount of carbon that will be sequestered in the project. Registration of the area as a carbon farming project was approved in early 2017, after which TREAT community volunteers planted and mulched 5,000 seedlings of native tree species.

During the first year of the pilot project, the 1.6 hectare planting was calculated to have sequestered over 44 tonnes of carbon dioxide equivalent (tCO2-e). The amount of carbon stored in the tree planting project (the carbon stock) was calculated using the standard Full Carbon Accounting Model (FullCAM), consistent with the rules set out for the Reforestation by Environmental or Mallee Plantings-FullCAM Methodology. This is one of several approved methodologies and would probably be best suited to most biodiversity plantings in our region.

In order to satisfy the requirements of the carbon farming program, we needed to keep records of many of the on-ground methods used in the project, including:

Estimated greenhouse emissions from these activities were 1.5 tCO2-e for the first year of the project. Once this was deducted from the calculated sequestration, the overall carbon sequestration value for the project was 43 tCO2-e.

Freemans Forest

TREAT volunteers planting seedlings in 2017 for the Freemans Forest carbon farming pilot project.

Could carbon farming costs be balanced by carbon credit earnings?

In addition to the costs involved in planting and maintaining the trees, the other main cost associated with being a carbon farm is the periodic, compulsory project audits which are the main way of ensuring that carbon farming projects comply with program rules. There are typically three audits scheduled during the project and these have to be undertaken by a registered auditor. At current prices, audit costs may come in between $30,000 and $50,000 over the lifetime of a project! The auditor used in the pilot project charged a comparatively favourable rate because of the community-based nature of the project and because a considerable amount of the preparatory work for the audit was already done by TREAT.

Using the approved FullCAM accounting method, one hectare of biodiversity planting on the Tablelands is calculated to sequester 790 tCO2-e over 25 years which would earn 790 carbon credits (Australian Carbon Credit Units (ACCUs)) over 25 years. The rate of carbon sequestration changes over time, with higher rates of accumulation in the earlier years of the planting. Under the current program, carbon credits can only be claimed for 25 years and any carbon sequestered by the continually growing forest cannot be claimed. Now, the price paid for those credits could be as low as $12/ACCU, which was the price being paid by the Federal Government in their abatement contracts during the first year of the pilot project. However, most biodiversity plantings will be too small to enter into a contract with government and anyhow would be likely to fetch a higher price on the Voluntary (or Secondary) market. There is no fixed price for an ACCU on the Voluntary market because the price paid depends on the value that each buyer places on the carbon credit. During 2018, the average price paid for an ACCU on the Voluntary market was around $18. Under this scenario, one hectare of biodiversity planting would earn just over $14,000 in 25 years (i.e., at $18/ACCU for 790 tCO2-e). These earnings would not offset even the auditing costs of such a small project. But remember, this is for a small, one-hectare area of planting, a fairly pessimistic price for carbon credits, and is based on a particular method for calculating carbon stocks.

Factors affecting the cost and income of carbon farming using biodiversity plantings

In the pilot project we looked at various scenarios that had different combinations of the main factors that affect economic returns from carbon farming using biodiversity plantings. The two main factors that affect costs are 1: whether or not there is funding for the planting and 2: the cost of the audit. In the calculations below we've used an approximate planting cost of $33,000 per hectare, comprising site preparation ($2,200), seedlings and planting ($17,800) and maintenance until canopy closure ($13,000), though we know this can vary depending on site conditions, weather and other factors. We've presented figures here based on two audit cost scenarios - High ($50,000) and Low ($30,000). For community-based, biodiversity planting carbon farming projects there might be a good chance of lower audit costs.

The two main factors that affect the income for carbon farming projects are 1: the size of project and 2: the price received for carbon credits. Increasing project size directly increases income because the number of carbon credits earned increases proportionally with size. Also, the cost per unit area of audits declines as project size increases. Experience in the pilot project and discussions with the auditors suggest that audit costs would be likely to remain similar even for substantially larger project areas, though we can't be sure that there isn't a threshold project size when the audit cost increases again (for example if the project was very large, took in areas with different characteristics, or crossed multiple property boundaries).

The table below shows a selection of different plausible scenarios resulting from different project characteristics. Scenarios 2-13 mostly show the minimum project size (rounded up) that would be needed to deliver a positive economic return on a project as the other characteristics vary. There are obviously many other possible values for characteristics, as well as additional costs that could be included to understand the economic outcomes of projects with different characteristics. We've chosen to present these ones to highlight the influence of changing certain characteristics. During the pilot project we developed a calculator that can be used to determine economic outcomes by entering any value for cost of planting, audit cost, project size, carbon price, as well as things such as administration costs.

This table gives a guide to economic outcomes under selected plausible scenarios resulting from different project characteristics. The possible values for each of the factors are:- 1: Funding for planting (Full (all costs covered), Partial (maintenance not covered) or None ($33,000)); 2: Audit costs (Low or High); 3: Carbon Price (Low or High); and 4: Project size. In all cases, it's assumed that the project sequesters 790 tCO2-e per hectare over 25 years. It's assumed that the full cost of biodiversity planting is $33,000, though we know this can vary depending on site conditions, weather and other factors. Administration and other costs are not accounted for. ACCUs are Australian Carbon Credit Units. This information is a guide only and should not be used as a basis for business or investment decisions.

ScenarioFundingAudit Cost Carbon priceProject size
Planting costsAudit Cost TOTAL COSTSACCU's
over 25 years
1FullLow High10$30,000$30,000790$30$23,700-$6,300
2FullLow Low20$30,000$30,0001580$20$31,600$1,600
3FullLow High20$30,000$30,0001580$30$47,000$17,400
4FullHigh Low40$50,000$50,0003160$20$63,200$13,200
5FullHigh High30$50,000$50,0002370$30$71,100$21,100
6NoneLow Low4$33,000$30,000$63,0003160$20$63,200$200
7NoneLow High3$33,000$30,000$63,0002370$30$71,100$8,100
8NoneHigh Low6$33,000$50,000$83,0004740$20$94,800$11,800
9NoneHigh High4$33,000$50,000$83,0003160$30$94,800$11,810
10PartialLow Low3$13,000$30,000$43,0002370$20$47,400$4,400
11PartialLow High2$13,000$30,000$43,0001580$30$47,400$4,400
12PartialHigh Low4$13,000$50,000$63,0003160$20$63,200$200
13PartialHigh High3$13,000$50,000$63,0002370$30$71,100$8,100

A few hectares of biodiversity planting could deliver economic returns as carbon farms

Because the number of carbon credits earned from a project increases with its size (i.e., a two-hectare project earns twice as many ACCUs as a one-hectare project), the costs of auditing may fairly rapidly be offset in larger projects. Scenario 1 in the table shows that, for a small project only one hectare in area, it wouldn't be possible to break even over 25 years, even if all planting costs were covered by grants, audit costs were low and a high price was paid for carbon. By contrast, a two-hectare project would at least break even under the same conditions (scenario 2) and could potentially yield substantial returns if high prices were paid for carbon credits (scenario 3; more on higher prices for carbon credits later). Scenario 3 is the best case scenario, with minimum costs and maximum income, under these characteristics. If audit costs were high, a project approaching 4 ha would be needed to turn a profit if the carbon price was low (scenario 4), while a 3 ha area would deliver a substantial return if the carbon price was high, even with a high audit cost (scenario 5).

Under this best case scenario (#3), 2 hectares of biodiversity planting could deliver $17,400 over 25 years. Increasing the size of a project with these characteristics would continue to increase the profit margin assuming constant planting (zero) and audit ($30,000) costs.

A carbon farming project area could include multiple different planting areas on one property, or even across different properties. Combining different planting projects into one carbon farming project is called 'aggregation' in the program and could be a way to use typically small biodiversity plantings to get the economies of scale needed to deliver economic returns on carbon farming projects.

In scenarios where there is no funding for planting (# 6-9 in the table), larger project areas (4-6 ha) are generally needed to deliver a positive economic return over 25 years, although a 3 ha project will be profitable if audit costs are low and the price for carbon credits is high. What this tells us is that, even if there was no funding for tree planting, it would be possible to break even financially as a biodiverse carbon farm.

Even if there was no funding for tree planting, it would be possible to break even financially as a biodiverse carbon farm if the project was three hectares in size, audit costs were low and the price received for carbon credits was high.

The thing with biodiversity plantings on the Tablelands is that a substantial proportion of the costs is usually covered by funding from grants, and community volunteers contribute generous amounts of time and labour; in the nursery, doing site preparation, and planting. While funding for tree planting appears to be declining, tree planting has been established in Australia's consciousness as providing society with environmental, economic, social and cultural benefits, and it seems likely that tree planting projects will continue to be funded, at least in part.

If there is a shortfall in funding, it's often for ongoing maintenance - anyone who's planted in the tropics knows the outcome of ignoring weed control for a wet season. Economic returns on partially-funded projects where ongoing maintenance is a cost to the project are shown in scenarios 10-13. Two to three hectares is enough to generate income with all combinations of project characteristics, except when the audit cost is high and the price paid for carbon credits is low, when a 4 ha project would be needed to just break even.

A higher price for biodiverse carbon sequestration?

On the Voluntary market, the price paid for carbon credits can vary a lot depending on how buyers value the credits. There is currently no way to distinguish carbon credits earned by carbon farms with additional values for biodiversity; credits earned by a monoculture plantation which may have only limited value for biodiversity, would potentially fetch a similar price to credits accrued from a biodiversity planting.

It's feasible that higher prices could be secured for 'biodiverse carbon sequestration' - that is, where the planting has additional benefits for biodiversity. Our biodiversity plantings are obvious candidates for this, delivering local biodiversity value, and with potential biodiversity benefits at regional, state and national scales. If biodiversity plantings could earn higher prices for the ACCUs they accrue, then greater economic returns would be gained from the same project area, or audit and planting costs could be covered from smaller project areas.

This would likely involve some sort of marketing as well as a reliable system for certification. It could be possible, for example, to develop a system for accrediting projects that use a recognised biodiverse planting method as 'biodiverse carbon' projects, which would add value to the price paid for ACCUs earned. Terrain NRM is currently working with the Queensland Land Restoration Fund to understand how biodiversity co-benefits of planting in the Wet Tropics could be quantified and certified, using a pilot study into a 'Cassowary Credit', which could be separate and additional to carbon credits.

A different method for calculating carbon stocks in biodiversity plantings

As described, there are strict rules for estimating the amount of carbon sequestered in a tree planting project. We used the standard equations in the FullCAM model for the pilot project, though it is possible that this method underestimates the amount of carbon stored in biodiversity plantings because FullCAM doesn't take into account the potentially large variation in carbon stocks between vegetation types, land zones and regions.

Using a method to directly calculate carbon stocks in biodiversity plantings would resolve the question of whether or not FullCAM adequately represents carbon in these projects, though this would involve destructive sampling to measure the carbon in leaves, twigs, branches, stems and roots and would require specialist equipment and skills. Working with research organisations to gain a better idea of the actual carbon stocks in biodiversity plantings could be a pathway to earning more ACCUs for biodiversity plantings of a given size, increasing the income potential for biodiversity plantings. An important step in this process would be having the new accounting method accepted and formally approved as part of the carbon farming program.

What have we learned from the pilot project?

The lessons from the Freemans Forest pilot project are documented in a fairly hefty, 90-page written report which will be useful for people who are considering carbon farming. This report carefully explains the steps for registration, record keeping, reporting and auditing and has links to supporting information, as well as the templates used in the pilot project to keep records. There is information about the different accounting methodologies and detailed instructions on how to use FullCAM to calculate carbon sequestration. The document also sets out the calculations used to work out the 'break even' price for carbon credits under different funding scenarios. One of the recommendations for anyone serious about engaging with the carbon farming program is to double-check the relevant websites and triple-check that you have found the most up-to-date information; during the pilot project we found several cases of conflicting and outdated information still linked to the program website. It's also worth considering the need to commit to managing and protecting the carbon stocks in the carbon farm for at least 25 years. Severe damage or loss of carbon stocks (from cyclones for example) could mean that the value of carbon credits already claimed would need to be repaid.

It's been a team effort to develop a clear understanding of the carbon farming program and to deliver the pilot project. Dave Hudson has done many, many hours of often frustrating and brain-bending work to unpick the complex rules and guidelines associated with the program, to negotiate with the auditors, question lawyers and complete the registration and reporting paperwork, among other things. Dave Skelton really sunk his teeth into FullCAM and developed a sophisticated understanding of the different options and outcomes for calculating carbon sequestration for tree plantings. Larry Crook did the GIS mapping for the registration and Frans Arentz did the original FullCAM analysis for the registration. Mark McCaffrey did the site preparation and on-ground maintenance of the Freemans Forest carbon farm and kept associated records needed to satisfy the reporting requirements of the program.

TREAT and like-minded people will continue to plant trees, even if their role in absorbing carbon from the atmosphere isn't formally recognised or remunerated. Carbon farming does present a practical option for generating income from biodiversity planting in our region under certain circumstances, and could unlock potential for biodiversity planting on a larger scale. To make this a reality, our tree planting community will need to think more about the logistics of aggregation for larger project areas, work with the Queensland Land Restoration Fund and other groups interested in increasing the price for biodiverse carbon credits, and consider options for directly measuring carbon stocks in biodiversity plantings.

How Does the Possum Cross the Road?

Angela McCaffrey


Some of you will remember the building of the East Evelyn Road 20 years ago, with three large wildlife tunnels being built into the structure, and revegetation plantings being done at the openings to the tunnels. It was near the Millaa Millaa Lookout and today the properties on both sides of the road, next to two of those tunnels, belong to South Endeavour Trust (SET).

Tim Hughes from SET has recently set up some camera traps to see what if anything is using the tunnels via the rope that passes through each of them. He has sent some photos to TREAT, and this photo shows a possum traffic jam!

A Curious Cassowary and IBM

Sigrid Heise-Pavlov

Cassowaries are known to be very curious, but humans are as well. In this story the curiosities of both came together.

For several weeks in July 2019 an almost mature cassowary (just its rear end was still brownish) was lingering around my shed at 'Iggies Nature Refuge' which adjoins Mt. Hypipamee National Park to the east. Some days the bird turned up as early as 8 am and watched everything that was going on. It stared at me when I had my breakfast on the veranda, was intently observing when I worked on the computer and watched my every movement when the truck was loaded to leave the property. Often it disappeared into the forest at around 4 pm to come back the next morning. Some days, however, the bird would just 'say Hello' in the morning, then disappear into the forest to turn up again at 3.30 pm to 'update' itself about what had been happening in the meantime, and stay around until dark. Although I twice heard the deep drumming sound from the bird, it was not aggressive, just very curious.

Staying around the shed for so many hours was not without consequences. Droppings from the bird started to accumulate. When there were seven large droppings, my curiosity was triggered. What had this bird eaten? The forest appeared to have a lack of fruit in July, meaning that the bird should have needed to venture out over long distances to find some fruit. But the bird was seen spending many hours near the shed. To answer this question, I picked up the seven droppings and took them one Friday morning to the Lake Eacham nursery. Besides TREAT members, students from the School for Field Studies (SFS) were also at the nursery on this Friday, and they were given the delightful job of sorting through the droppings to find out what the bird had eaten. Of course, some of the students did not consider this job as exciting as it was supposed to be. But when the words 'dropping', 'poo' or 'scat' were replaced by 'important biological matter' (also known as IBM), some changed their mind and got on with the job. The sorted seeds were identified by Nick Stevens, the ranger in charge of the nursery, and Angela McCaffrey, president of TREAT. Most droppings contained seeds from Cryptocarya oblata and C. densiflora, different sizes and sometimes just halves of seeds. But there were also some flower remains from Syzygium cormiflorum and 62 tiny immature seeds of a Quandong species.

Another cassowary dropping had been picked up from the access road to the School for Field Studies two days prior to the Friday at the nursery. This location is near the Gillies' Range Road and thus the content of this dropping differed from the previous droppings. It contained 328 seeds of Acmena smithii and 30 seeds from Halfordia scleroxyla. The dropping also contained quite a few rocks. Based on these findings it appears that the forest around the School for Field Studies does not provide as much large fruit as the forest at Iggies Nature Refuge. However, both birds had found fruit at a seemingly 'fruit-poor' time.

Thanks to the students from SFS for 'dissecting' the droppings and to Nick and Angela for identifying the contents. Some of the seeds will be kept at the nursery to develop into seedlings for the next planting season.

Cassowary SFS Students

Cassowary and fresh dropping, SFS students sorting IBM

Planting up the old Millaa Millaa Lookout Road

Larry Crook

On a bitterly cold, overcast and miserable day in early June, a small dedicated group planted 600 trees on the old Millaa Millaa Lookout road. The decommissioned road forms a linear canopy gap in 'Misty Mountains Nature Refuge' (owned by South Endeavour Trust). The aim of this project is to restore the habitat linkage for wildlife movement. The project was funded by the Tablelands Regional Council (TRC) as an offset.

The planting site was approximately 100m long and 10m wide. Site preparation had involved eradicating weeds and ripping up the old asphalt road using a D7 dozer with a triple tine 1.5m wide ripper attachment. The rip lines were to a depth of about 300-400mm. These rip lines were staggered approximately every 25m to help reduce the speed of run-off water during major rain events. Once the rip lines were established, Mark McCaffrey was contracted for site preparation, including: hole digging plus fertiliser and water crystals placement. The planting was completed by Mark and Angela McCaffrey, myself, and two TRC staff; Kylie Freebody and Doug Stewart.

Approximately 20% of the 600 trees planted were either pioneers or quick-growing species such as Homalanthus novoguineensis, Mallotus paniculatus, Alphitonia petriei and Elaeocarpus grandis. There was a higher than normal density of trees in this planting to compensate for an expected higher mortality rate, that may result due to the late planting and the harsh gravelly conditions at this site. Mark has a further contract for maintenance of the site.

Millaa Lookout Millaa Lookout

Millaa Lookout planting. Photos: Mark McCaffrey, Kylie Freebody

Hand Weeding at Freemans Forest NR

Angela McCaffrey

Hand Weeding

During the recent infrastructure upgrades at the Lake Eacham nursery there were a couple of weeks when the nursery could not open on Friday mornings and this coincided with visits from School for Field Studies students. So rather than cancel these visits, we took the opportunity to arrange some much needed hand-weeding at Freemans Forest Nature Refuge. TREAT volunteers and students came along to pull up weeds, mainly from the edges of the 2012 and 2014 plantings where they join with the track and extra light gets in. Simon and I cut and pasted some of the larger weeds such as Wild Tobacco.

The canopy is developing well over the track so this should not be a long term problem. Similar events will be arranged next to other areas of track as plantings go beyond their usual three years of maintenance, and we hope to plant some edge-loving understorey plants such as native gingers once the weeds have been reduced.

TREAT Field Day - Wairambar Rainforest

Carey Robinson

After months hidden in the mist, the Topaz sun shone on twenty-five TREAT members gathered on the afternoon of Saturday 22 June for a field day in the Wairambar Rainforest.

Our hosts Paul and Roberta Michna purchased their 24 hectare rainforest property in 2002. The property is classified as regional ecosystem type 7.8.2 and lies at 700m altitude. It is named after the ecosystem of Wairambar Creek, which forms one of the property's boundaries with the Wet Tropics World Heritage Area.

At our gathering place at the corner of Doonoquienbar Road and Wairambar Creek Road, Roberta acknowledged we stood on the traditional country of the Ngadjon people and that the area was a significant Nadjonji campsite and trackway. Roberta also outlined Wairambar's more recent history, including prospecting for alluvial gold in the 1880s and 1960s. After the initial gold exploration there was timber felling, and later cattle grazing and crop experimentation on nearby properties. The cropping included a small tea plantation on the edge of Wairambar. In 1928 the neighbouring property was the location of the locally infamous 'Boonjie murder', the unsolved death of a young labourer.

The rainforest here is of scientific interest for its high degree of endemism of primitive Gondwanan flora and the refugium status of many parts of the ecoregion. The area has a diverse topography, with a range of microclimates and a variety of soils including alluvial, granitic, basaltic and marine sediment-derived metamorphics. Roberta and Paul and rainforest researchers have so far identified over 300 species of plants on the property.

We started our tour walking along Wairambar Creek Road, conditions underfoot neither dusty nor muddy after a few rain-free days. This route took us past the edge planting along Doonoquienbar Road, commenced in 2002 after the removal of bramble and lantana. Roberta explained that the canopy in this area has recently developed a 'forest feel'. A short distance further on stands Paul and Roberta's original weekend retreat, a caravan now beginning to blend into the trees.

We continued along Wairambar Creek Road to see the tea invasion revegetation project, where a campaign is underway against tea seedlings (Camellia sinensis) still emerging under the rainforest canopy from the historical tea plantation. Roberta and Paul tried using herbicide on the tea seedlings, but found that to be both cost-prohibitive and ineffective. They are now combatting the tea by cutting it back frequently to encourage competition from rainforest plants, and by planting shade-loving rainforest species, some sourced from TREAT and others grown from seed gathered on the property.

Paul and Roberta mark the trees they have planted with a different coloured tape for each year, to distinguish them from naturally occurring seedlings. Brown Pine (Podocarpus dispermus) is one of the species grown from seed collected at Wairambar, and it has grown particularly well in this area. We also saw Zamia Fern (Bowenia spectabilis) and Apricot Myrtle (Pilidiostigma tropicum), growing amongst fallen Black Wattle (Acacia celsa) seed pods with their curling patterns of white and brown.

We walked back to Doonoquienbar Road, where Roberta pointed out the new wildlife-friendly fencing along the property boundary. This fencing, comprising four strands of plain wire, has replaced the barbed wire fencing that protected the early plantings from cattle.

Roberta and Paul are now revegetating the road verge on the opposite side of Doonoquienbar Road, a space of about 15 by 100 metres, bordering a paddock infested by Navua sedge. Paul explained that he used glyphosate to treat the Navua sedge and then a variety of techniques to encourage revegetation.

Field day Doonoquienbar Road

Walking along Doonoquienbar Road

This site is exposed to wind, so Paul and Roberta have protected their seedlings by using individual tree guards and black plastic along the paddock fence, and by planting cuttings of fast-growing Beach Hibiscus (Hibiscus tiliaceus).

They have collected cassowary scats containing local seeds for planting. Species include the naturally occurring Pink Ash (Alphitonia petrei), and Aristolochia acuminata, a vine which is a food plant for the larval stages of the Cairns Birdwing Butterfly and the Red Bodied Swallowtail Butterfly. Roberta and Paul have also spread hay mulch to suppress weeds and encouraged pumpkin vines to provide green mulch (and soup).

We had two options for the remainder of our tour. One group walked with Paul along Doonoquienbar Road, along the property's boundary, then back through the rainforest. The other group walked with Roberta along a track paralleling the driveway, past wildlife habitat boxes, to the Michnas' home 'Studio Nimbus'.

I chose the boundary walk, during which Paul drew on his geology expertise to explain the local landforms and alluvial gold deposits, noting for any potential prospectors that these were never plentiful and are now thoroughly depleted!

We followed a track downhill into the mature rainforest, then turned along the path of an old water race engineered by gold prospectors to bring water through a tunnel from the other side of the hill.

Wildlife observed in this area includes Herbert River and Lemuroid Ringtail Possums, and Paul and Roberta have also identified thirteen cassowaries. On this occasion, in the mid-afternoon quiet time, the rainforest creatures stayed out of our view.

We admired many beautiful large trees as we made our way along the hillside, including Watergums, (Syzygium gustavioides) with distinctive reddish bark and adventitious roots, and a Bumpy Satinash (Syzygium cormiflorum) with flowers spangling its trunk. Nearby, Paul and Roberta have planted several Stockwellia trees (Stockwellia quadrifida) and fenced them off to protect them from feral pigs that occasionally maraud the area.

Field day Red Cedar stump

Red Cedar stump. Photo Carey Robinson

On the steep slope above the track stands the massive trunk of a Red Cedar (Toona ciliata), thought to have been logged in 1928. The stump has held its form so well that we could see the holes chipped out by loggers to hold springboards, on which they stood to cut the trunk above its buttressed base.

From here we walked up to the driveway and Studio Nimbus, the Michnas' three level home designed specifically for living in the rainforest. From its balconies, there are views through the canopy and to Mt. Bartle Frere in the distance. Nearby stands Paul and Roberta's earlier, post-caravan dwelling of two shipping containers, now a base for rainforest researchers interested in open source knowledge.

At Studio Nimbus we enjoyed a delicious afternoon tea and information displays. The displays included maps, species lists, rainforest fruit, seed pods, leaves and rocks, and a recently identified cutting of Crispiloba (Crispiloba disperma), a stunning shrub with frilly cream flowers and a delightful scent.

Warm thanks to Roberta and Paul for their generosity in sharing with us their time, knowledge and inspirational progress in regenerating the beautiful Wairambar Rainforest.

Field day Crispiloba disperma

Crispiloba disperma. Photo Carey Robinson

Nursery News - June 2019

Nick Stevens

We have been having a very busy year so far at the nursery with some major revitalisation works progressing over the last 6 months, including several large maintenance jobs and a Capital Works project to resupply the Lake Eacham Base and Nursery with filtered and treated water. Over a number of years the nursery has been experiencing reduced water flow and pressure due to internal corrosion and gradual blockage of the steel supply line which had been in service since around 1986. Water quality was also an issue and we were no longer able to source parts for our old ultra-violet disinfestation system commissioned in 1995.

Works on this project have included replacement of the raw water pipeline to a new storage tank above the nursery, the addition of a new pump and filtration shed housing a multistage, twin pressure pump and dual ultra-violet filter units with particle and chemical filtration, which now supplies the entire base allowing us to run any amount of water at the base and nursery simultaneously without affecting the quantity or quality of the nursery's irrigation. All that is missing are the fluffy dice!

Other works around the nursery have seen the replacement of the concrete floor in the greenhouse area. The old concrete floor had been difficult to keep clean from algae due to its eroded surface from years of chemical erosion caused by the acidity of potting media, constant watering of plants in the greenhouse and hosing down the surface to prevent build-up of debris. As well, there were some uneven sections and cracks which were trip hazards and which promoted poor drainage. Rust around the footings of the pylons supporting the roof structure of the greenhouse also needed to be dealt with and the new footings will be easier to maintain into the future. The nursery building housing TREAT's office and kitchen has also received a long overdue coat of external paint, with repairs to gutters, and the deck area also getting an overhaul.

The back fence around the nursery compound is in the process of being replaced and has been quite a complex bit of work, so far requiring the expansion of the bottom edge of the bay 3 plant hardening area, formation of a new gravel pathway complete with sub-soil drainage, the installation of a retaining wall and concrete set posts, and incorporation of the new nursery water supply lines and the irrigation control valve boxes, also set below the gravel surface. On completion of these groundworks and fence installation, bay 3 will finally be able to be fitted with new weed matting and the new plant racks throughout.

Congratulations and special thanks must go to Peter, Simon, Stuart and Mick for their efforts on the design and implementation of this project which will enable the nursery to continue to operate to best practice principles for many years to come. It must also be mentioned that a large part of the implementation of these works has involved the constant shuffling of whole racks of plants, including dismantling and reassembling the racks themselves, at each stage of the project, making it very labour intensive but allowing nursery production to continue with as little interruption as possible.

Nursery Nursery

The gleaming new concrete floor, Nursery outside bays.

Geoff wrote this poem for the occasion of the Memorandum of Understaing signing in February.


Gardening Australia, it's on your ABC
We watch it every Friday night, as soon as we've had tea.
They show us lovely gardens just so perfect and complete
With curving paths and pristine lawns, all manicured and neat
Not a flower is out of place, no weed disturbs the scene
Their veggie plots produce like mad, in every shade of green
And we sit in our armchairs, bewildered and nonplussed
This broadcast's from another world - it can't be meant for us.

We marvel at the way the owners take their barren waste
And make it an oasis in almost unseemly haste
Every wall and trellis they build vertical and true
I can't believe they don't fall down as mine all seem to do
Their compost bins always turn out these warm, nutritious brews
While mine just sit and sulk and then become this rancid stew.
The worst that ever happens is perhaps a little frost
In winter, or a touch of scale - they really make us cross.

Nowhere in all the episodes - we've watched it now for years -
Have we ever seen the sorts of things that bring us close to tears
Not once has any gardener raced into camera shot
In hot pursuit of swamp hens; not once, I kid you not.
This simply does not happen in that regulated world
There's never any evidence of rakes and curses hurled
At flying fox or possum that have made off with their fruit
At most they may have got a little mud upon their boot.

Where are all the pademelons, eating their new trees?
And neighbours' dogs despoiling paths - their life is such a breeze.
I've yet to see a cane toad lurking in some lovely pond
Or fouling up a water dish - the list goes on and on
Their trials and tribulations are all of the gentler kind
No rabbits, neither bandicoots that you or I might find.
Their lawns look like the sort of place you'd put up croquet poles
While mine looks like a golf course.  Every metre, eighteen holes.

They love to mulch, go on at length how it keeps moisture in,
Suppressing weeds, and all that's true.  But never have we seen
A trail of bark from garden bed, spread across the ground,
Destined to become a part of Mr Turkey's mound.
Such things are never seen whenever we watch Costa's show
All effort is rewarded, they get everything to grow
No endless hours are spent replacing veggies shared with pigs
Or making tree guards to protect where bandicoots might dig.
It's very hard to get that sort of pleasantness up here
When rain arrives in summer and we get eight feet a year
When pruning can get out of hand with all those brand-new shoots
And weeds fill up the garden while you're pulling on your boots.
So I might send this to Costa?  I think he should be told
It isn't just advancing years that make us seem so old
It's all the extra work we do to get things looking right
And despairing that we'll ever match what we'll see Friday night.

Geoff Errey
February 2019

Fruit Collection Diary April- June 2019

SpeciesCommon NameRegional EcosystemCollection Dates
Acronychia crassipetalaCrater Aspen7.8.420/03/2019
Alyxia oblongataPrickly Alyxia7.8.312/04/2019
Athertonia diversifoliaAtherton Oak7.8.210/04/2019
Brachychiton acerifoliusFlame Tree7.8.230/03/2019
Castanospermum australeBlack Bean7.3.1012/06/2019
Celtis paniculatuaSilky Celtis7.8.324/04/2019
Cryptocarya onoprienkoanaRose Walnut7.8.426/06/2019
Eleaocarpus bancroftiiKuranda Quandong7.8.314/03/2019
Eupomatia laurinaBolwarra7.8.22/05/2019, 22/05/2019
Ficus leptocladaAtherton Fig7.8.420/03/2019
Ficus racemosaCluster Fig7.3.1012/06/2019
Ficus septicaSeptic Fig7.8.222/05/2019
Ficus watkinsianaWatkin's Fig7.8.420/03/2019
Karribina biagianaRed Carabeen7.8.210/04/2019
Mackinlaya macrosciadeaBlue Umbrella7.8.31/04/2019
Melicope elleryanaPink Euodia7.8.223/04/2019
Melicope jonesiiEvodia7.8.213/05/2019
Omphalea queenslandiaeOmphalea7.8.11/05/2019
Pitaviaster haplophyllusYellow Aspen7.8.212/04/2019
Pittosporum revolutumHairy Pittosporum7.8.214/06/2019
Syzygium graveolensCassowary Satinash7.3.1030/03/2019
Vitex queenslandicaVitex7.8.310/04/2019
Zanthoxylum ovalifoliumThorny Yellowwood7.8.29/05/2019

Species and Common names taken from 'Austrailan Tropical Rainforest Plants Edition 7' online key:


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