The Tigercat M726G wheeled mulcher creating a firebreak in old growth fynbos while the fire continues to burn in the background.
Quick thinking and quick action by an MTO forester and a mulching contractor stopped the spread of a wildfire that broke out in very old fynbos near Covie in the Western Cape recently.
MTO forester Koos Lourens called Clinton Payn of Savithi Mulching for assistance in stopping the fire that was threatening surrounding areas including rural dwellings and MTO’s Lottering plantation. Savithi has been busy in the area for several months clearing overgrown compartments for MTO that had been damaged in an earlier fire using a Tigercat M726G wheeled mulcher. It was a Sunday when most people are taking it easy, but quick action was needed to stop the fire before it ran away into the old growth fynbos.
Watch the Tigercat mulcher in action as it creates an emergency firebreak...
Aerial support was used to cool the fire down allowing the Savithi team to move in with the Tigercat mulcher to create a firebreak of around 1 km long and around 25 metres wide that ultimately stopped the fire in its tracks. The speed of the large and powerful wheeled mulcher was key in getting the job done quickly before the wind could pick up or change direction and turn it into a really dangerous spreading fire.
Clinton said the fynbos was so dense and high that the operator couldn’t see the ground he was mulching and in some places he had to assess the risks on foot to make sure there were no big holes or rocks that could damage the machine.
According to MTO forester Nico de Waal who was the fire boss, the fynbos in that area is around 25 years old and is well over head high, and creates a very hot fire. He said it is not possible to use ground forces to create a firebreak in those conditions, and so the best option was to bring in the mulcher which reduced the fynbos to a mulch carpet in buffer strips that stopped the fire in a matter of hours.
This aerial photo shows the strategic placement of the firebreak that stopped the wildfire from spreading.
Nico said that MTO has been busy working with other stakeholders including the Southern Cape and Sarah Baartman FPAs to do block burns in an effort to create strategic fire breaks that would prevent the spread of large, destructive wildfires such as those that occurred in the southern Cape in 2017 and again in 2018. He said that most of the wildfires come from beyond their boundaries and it’s part of their Integrated Fire Management strategy to fight any fire that has the potential to threaten their plantations, wherever they occur.
Clinton said there has been a lot of interest in utilising Savithi’s services to mulch fire breaks and reduce fuel loads in the southern Cape which has been plagued by big, destructive fires over the past few years. Another benefit of mulching is that it opens up areas to allow vehicle access for forestry operations or for fire suppression. Land owners and land managers in the region have realised that proactive action is required to reduce fire risk in this fire-prone landscape.
This is the Tigercat M726G wheeled mulcher operated by Savithi.
New association for wildland firefighters launched
A new association for Wildland Firefighters has been launched in South Africa. The Association for Wildland Firefighters (AWF) represents the wildland firefighting industry and associated professionals in Southern Africa.
“Numerous investigations into some disastrous fires in Southern Africa highlighted the need for a formal body to represent the needs of the wildland firefighter. The AWF aims to develop the knowledge, skills, understanding and competence of wildland firefighting in South Africa,” says Etienne Du Toit, the chairperson of the AWF.
Du Toit says the organization aims to improve the standards of safety and the working environment for firefighters in the sector in which its members operate.
The Association is registered as an independent, non-governmental, non-profit organisation. Any person or organisation associated with the wildland firefighting/integrated fire management fraternity qualifies to be members.
Du Toit says that climate change has resulted in a significant increase in wildfire risk, not only to responders but also to civilians.
“Monetary losses and other damages as result of these fires annually exceeds hundreds of millions. More needs to be done to address these risks. This is where the AWF comes in, an organisation that aims to share learning in such a manner that it promotes professionalism, reduces responder and civilian risk and at the same time allows for continuous improvement in all aspects of integrated wildfire management.”
The new association specifically addresses the needs of the wildfire fraternity.
“Until now, no other association specifically addressed the needs of the wildfire fraternity, there are similar associations but these are more focused on the structural firefighting sector,” says Du Toit.
The founders of the organisation come from a variety of backgrounds, including the fire service, forestry and conservation sectors and include business development practitioners with vast practical experience in these sectors.
“This Association seeks to enhance synergies between the various entities responsible for wildfire and integrated fire management, and one of the main aims is to professionalise the wildfire fighting industry in SA,” he said.
For more info contact Tessa Oliver at email: info@wildlandfire.org.za
Paraquat - widely used in South African forestry to prepare tracer belts before burning firebreaks - is facing world-wide bans, forcing foresters to reach for the old-fashioned hoe. GAYNOR LAWSON reports.
It sounds so benign: “A non-selective herbicide - an aqueous solution contact herbicide for the control of annual grasses and annual broadleaf weeds in crops as listed and as a sugarcane desiccant. Inactivated on contact with the soil.” But this listed herbicide that contains Paraquat, “could have killed 2000 people” when maliciously used by a disgruntled employee to poison a tank of milk in the Cape in 2017, according to a News24 article. It is highly toxic.
Locally, Paraquat is extensively used to create tracer-belts as part of a fire management programme to prevent fires running out of control during the burning of firebreaks. The herbicide creates a boundary area devoid of vegetation before burning takes place. It is considered cost-effective, efficient and useful as it only desiccates the above-ground part of the vegetation (it leaves the root stock below ground unharmed), allowing for regeneration with the rainy season and thus preventing erosion or invasion by alien plants.
First produced for commercial purposes in 1961, Paraquat remains one of the world’s most commonly used herbicides, despite its potentially lethal impact on humans, either through deliberate poisoning or simply by working irresponsibly with it. It may be airborne when applied as a fine spray and can be spread through contact with clothing so it requires special training to ensure safe handling by users.
China reportedly experiences 5,000 deaths from Paraquat poisoning annually, although whether this is through accidental or deliberate poisoning is unconfirmed - Paraquat is known to be used in suicide attempts. It reputedly doubles the risk of Parkinson’s disease in those who come into contact with it, and the Michael J Fox Foundation issued an anti-Paraquat appeal on its website in October last year (the popular actor’s much-publicised battle with Parkinson’s has brought about heightened awareness of the disease): “Take action today to ban Paraquat. Your support can help protect people from environmental exposure to a known pesticide that increases the risk of Parkinson’s disease. We need your help to educate your Senators and Representatives…”
The appeal was posted in response to the reapproval by the Environmental Protection Agency (EPA) of several pesticides (including Paraquat) for use in the United States. The EPA reviews all herbicides and pesticides every 15 years to confirm they are safe for use, based on “assessments of human and environmental impact”. Despite its “well-documented harms”, the use of Paraquat in the United States “is at an all-time high, and it is one of only two pesticides still used in the United States that is either banned or being phased out in the European Union, China and Brazil”, according to the website.
Measures have indeed been put in place to control its availability. It cannot be bought or used in the UK (although, ironically, it is legally manufactured there), Thailand, Vietnam, Malaysia and the European Union (where it has been banned since 2007). It has been banned in Switzerland since 1989 because it is deemed too dangerous for use even when wearing protective clothing and equipment. In the USA, only commercially licensed users have access to it.
A complete international ban is apparently blocked by the US and developing nations whenever this is proposed. According to an article, “Poison on a plate”, which appeared in The Daily Maverick on 26 January this year, “It’s a shocking display of global north hypocrisy, allowing dangerous agrochemical companies to flood low- and middle-income countries for the financial gain and profit of European nations.”
The situation in South Africa In South Africa, plantations certified under the Forest Stewardship Council (FSC) may not use Paraquat in any formulation that is available on the market. Gerrit Marais of the FSC Southern Africa Office, says: “Paraquat has been on the FSC Highly Hazardous list since the first pesticide policy was published way back in 2006. The figure below provides information on the reasons why this is done i.e., acute toxicity. Use of the product is thus not limited but prohibited unless it is approved, via a formal FSC process, for temporary emergency use. The South African forestry industry used to have a special derogation (exemption) for the use of this active ingredient and product, but this expired in 2020…Traditionally, the only alternative (to Paraquat) was to hoe the tracers by hand. This is, however, not ideal from an environmental perspective as hoeing often leads to erosion and thus this option – especially on steep slopes - is most undesirable. Some certificate holders have used other systemic herbicides (such as Glyphosate), but here too, the entire plant is killed and the risk of erosion is increased. The South African forestry industry is looking at other options…”
The stance of the Sustainable African Forest Assurance Scheme (SAFAS) – which has been endorsed by the other global certification body, PEFC - is that Paraquat can be used for tracer belt preparation, providing strict control/mitigation measures are in place. Steven Germishuizen, SAFAS general manager, says: “SAFAS supports the use of Paraquat from an environmental perspective because it is the best solution for fire management in grasslands. However, we acknowledge that it is highly toxic, so in accordance with our risk-based approach, we insist on strict precautions as far as training, use of PPE and application methods go.”
Craig Norris, NCT Forest Technology Manager, adds: “In addition to what Steve has said, we encourage an integrated approach to chemical use. In other words, the use of agrochemicals is the last choice of action and must be defendable. Agrochemicals can be detrimental to human and environmental health and will only be used after due consideration is given to other options/mitigation measures: • Chemical control must be used in combination with above methods to minimise quantities used. • Strategy for reduction of chemical use must be implemented. • Chemical label specifications must be followed. • Recommended safety, training, application procedures must be adhered to.
Steven comments: “We also encourage the use of technology, such as drones, to keep people away from the chemical. We strongly encourage exploration into environmentally suitable alternatives that are less toxic.” There is some experimentation with drone spraying currently underway in an attempt to cut humans out of the Paraquat-handling process almost completely.
What is the history behind Paraquat use in SA? According to Dr John Scotcher of ForestLore Consulting in a report written for the FSC in 2014: “Burning green grass is not possible and, in any event, adversely affects biodiversity. In order to improve the safety aspects of burning firebreaks, a system of fire tracer lines was introduced which entailed the hoeing or ploughing of two parallel strips of vegetation approximately one metre wide (the fire tracer line) and 30 metres apart during the late summer to early autumn. These tracer lines are now devoid of vegetation and are used as lines from which to burn the intervening 30 metres (the firebreak) during winter when the grass is dry.”
The report continues: “Approximately 30 years ago, the use of chemicals was introduced as an approach that could be used where mechanical methods such as hoeing, ploughing or use of a brush-cutter was impractical and dangerous to use … normally on steep and mountainous terrain. Paraquat was first used in South Africa in 1982 by the nature conservation agencies responsible for the management of high-altitude grasslands in the uKhahlamba-Drakensberg Park, which is a registered World Heritage Site. The use of Paraquat in this mountainous region enabled the elimination of the historic use of hoed or ploughed tracer lines that resulted in soil loss and scars across the landscape, which even after 100 years are still visible to this day. Paraquat was soon adopted by the agriculture and forestry industry. Paraquat was ideal for use in conservation areas and later in no-till systems such as forestry and grazing lands since it only affects the foliage part of the sprayed plants, thus promoting intact root systems and preventing soil erosion. It also does not leach into groundwater since it is absorbed into clay particles and neutralised when it comes into contact with the soil … In the forestry industry, the use of Paraquat was seen as a best management practice because there was no need to continue with the damaging practice of hoeing or ploughing.”
The Forestry South Africa Environmental Guidelines for Commercial Plantations in South Africa (Version 4 2020, chapter 4) proposes the following approach to the preparation of firebreaks:
Mowing
Slashing
Burning
Desiccant chemicals (Paraquat) – on slopes greater than 20 per cent
Manual hoeing – now discontinued
Mechanical methods (ploughing) – now discontinued
The Wildland Fire Management Handbook for sub-Saharan Africa provides detailed advice on fire protection and advocates the use of ‘chemical surface sprays’ for the preparation of tracer lines i.e. Paraquat.
Paraquat may still be used by the man in the street, although a global shortage because of it being discontinued in many countries has sent prices rocketing. Is there an alternative?
Roger Poole, chairman of the Timber Industry Pesticide Working Group or TIPWG, says: “The forestry industry in collaboration with Professor Keith Little of Nelson Mandela University (NMU) has been researching and testing alternatives for the past nine years since the FSC first indicated that Paraquat would be prohibited. One alternative, pelargonic acid, has shown results similar to Paraquat as a desiccant and was heading for registration under Act 36 of 1947. Unfortunately, the manufacturer was involved with a company buy-out and the new owners changed the formulation of the original product that had been tested. Bridging trials were done to compare the new formulation to the original pelargonic acid; sadly the new formulation did not show favourable results and could not be registered. Glufosinate-ammonium is an active ingredient that is used in agriculture, classed as a partly systemic contact herbicide that is an alternative for tracer preparation - but supervision is imperative as over-application could result in it being more systemic than contact and grass root systems could be severely damaged. TIPWG has stated that Glyphosate formulations should not be used for tracer preparation as this active ingredient could result in a complete kill and thus erosion will occur, especially on steep terrain.”
Dr Scotcher adds in another factor - the human element of the spraying process: “When terrain is steep, the person spraying naturally slows down to navigate safely up or down the hillside, resulting in a higher application rate per unit area.”
Dr Gerhard Verdoorn, Operations and Stewardship Manager for CropLife SA, comments: “There is currently no herbicide with the properties of Paraquat apart from diquat which is also a bipyridinium compound with high toxicity. It is not registered for the purposes of industrial vegetation management like Paraquat is. A possibility is pelargonic acid but the dosage rates required to desiccate plants is much higher than what was originally anticipated and that makes it a very costly option. Furthermore, it is not registered in South Africa. Attempts with many other herbicides have all failed to emulate the effects of Paraquat. Glyphosate is registered for such purposes as making firebreaks but due to its systemicity, it kills plants completely which leads to terrible erosion.”
When asked about the slower progress of workers on steep slopes leading to over-application, he disagrees, saying: “Glyphosate is super-systemic and even with a low dosage (lower than label directions) it will kill plants completely, especially broad-leaved plants. Some of the tough monocotyledons like Cynodon will survive but most of the softer grass species are wiped out completely. Another issue is the problem of resistance development when sub-optimal dosages of Glyphosate are used for chemical mowing; although it is on labels of some Glyphosate-containing herbicides, it is the best catalyst for resistance development I have ever heard of and the crop sector is currently battling with Glyphosate resistance (Amaranthus palmeri, Amaranthus hybridus, Conyza bonariensis, etc).”
A desiccated tracer break ready for burning.
Is a total ban an over-reaction? “People are very quick to point fingers at the use of pesticides but are sadly ignorant of potentially toxic products they use daily at home and, which, if used incorrectly, can be fatal,” says Roger Poole. “Everyone loves coffee, but do they know that the caffeine in coffee's LD50 is 150-200 mg/kg?” {LD50 is the amount of a substance, given all at once, that causes the death of 50% of a group of test subjects; it is a way of determining the short-term poisoning potential or acute toxicity of a substance}.
“So why has no one died from coffee? Simply put, the risk of consuming lethal quantities in your morning cup of java is not possible so the risk of poisoning is reduced. Consider household cleaning detergents, has anyone ever read the label or safety data sheet of the detergents they have in their home? Are these locked away so the uninformed cannot access them? Are certain products kept separately so that they cannot react with each other? Bleach is one of the most commonly used products found in households throughout South Africa, but did you know that if bleach and vinegar come into contact with each other their reaction can cause chlorine gas? Whatever product you are using at home or in the workplace, be it a pesticide or a detergent, they can all be toxic if used or applied incorrectly.” His message is loud and clear - use Paraquat correctly to minimise potential risks!
Is a total ban on Paraquat likely in the near future? The Rotterdam Convention is scheduled to take place this year, although with the global COVID-19 pandemic, whether it goes ahead is uncertain. Poole says: “Paraquat is one of the many listed active ingredients for consideration to be banned worldwide and has been listed numerous times but never seems to be banned due to pressure from the large world economies. We wait in anticipation for the outcome, as we've done in the past.”
A year later on… It’s a year since an article entitled 'Weaning the forestry industry from its paraquat reliance' by Jacqui Meyer appeared in SA Forestry magazine. According to the article, “the next step is applying for an Emergency Registration under Act 36 of 1947, which Dr Gerhard Verdoorn of CropLife SA is currently assisting TIPWG with. With CropLife’s support and the information obtained from the bridging trials, we hope to have pelargonic acid available for the 2021 summer rainfall area fire season.”
Well, that was in March 2020, and in April 2021, Dr Verdoorn was doubtful about the predictions - for this fire season at least. “I am not sure this is going to materialise… if we are able to get our hands on pelargonic acid. It is quite expensive … and I wonder if it will make the grade for the timber industry.”
In the meantime, creating tracer belts using mechanical methods such as brush-cutters and tractor-operated grass-slashers is the norm, with some landowners and companies using Glufosinate-ammonium. “It’s been very difficult, with manual clearing and a return to traditional hoeing on flat terrain,” says Simon Thomas, Operations Manager for KZN FPA. So, what will the situation be by next year’s fire season? Is a total switch to drone-spraying a feasible option? Only time will tell.
Despite the fact that sawdust piles are fire hazards, they are very unlikely to spontaneously combust as a result of heat build-up as the composting process of pure sawdust is too slow. This argument was accepted by the judge in a court case in which a sawmiller was sued by a neighbouring landowner who claimed that a sawdust pile spontaneously combusted, causing a fire that damaged his plantation. DAVE DOBSON reports …
Background This case study deals with allegations of spontaneous combustion in sawdust heaps on the Defendant’s property that resulted in a fire that devastated a neighbouring commercial pine plantation.
The Client The client was the Defendant in this case; the owner of a property on which eucalypts were grown to supply a sawmill that processed the timber to produce pallets.
The sawdust arising from the milling operation was dumped at various localities on the property and not incinerated on account of the danger associated with this operation.
This case deals specifically with the claim by the Plaintiff that as a result of the manner in which the Defendant managed the sawdust, spontaneous combustion occurred. This lead to the wild fire that burnt the neighbouring commercial pine plantation belonging to the Plaintiff.
The Challenges A number of challenges arose in the case but the most important one related specifically to the sawdust. In the summons it was claimed that the sawdust piles constituted a fire hazard in that: • The Defendant had not intermittently layered the sawdust with soil. • The Defendant had not restricted the height of the sawdust heaps so as to avert or minimise the risk of spontaneous combustion occurring in the sawdust pile.
The Plaintiff claimed that these two omissions were largely the reason for the spontaneous combustion occurring.
A third claim was that the Defendant failed to maintain an effective firebreak around the perimeter of the sawdust piles. Such a firebreak - if implemented - would have contained the fire to the sawdust pile.
The Solution While sawdust fires are recognised as being a potential fire risk, SAFIRE Insurance Company Ltd. had at the time that this court action commenced (2012) never received a claim emanating from smouldering sawdust piles.
However there was a single incident reported to SAFIRE of a fire in a sawdust pile, but this was not the result of spontaneous combustion of the pile. This was a fire in sawdust at a sawmill on the farm Etterby in the Richmond district. This fire was extinguished by digging out the smouldering sawdust and dousing the area with water. The fire had entered the sawdust while the landowner was burning a firebreak around the sawdust pile.
Spontaneous combustion does at times occur at composting facilities when the compost heaps self-heat to temperatures high enough to ignite. In these instances no external heat source is required. In order for composting organic material to ignite very specific conditions are required. These are: • A C:N (Carbon:Nitrogen) ratio of 20:1 to 35:1 is required. Sawdust has a C:N ratio of between 300:1 to 400:1. The result of this is that the composting process for pure sawdust will be extremely slow. (Nitrogen is required to feed the micro-organisms that are responsible for the composting process. There is simply not enough of this nutrient for them to thrive!) • The moisture content of the compost heap must be greater than 50%. Below this percentage the composting process slows down. • Aeration is required for rapid, efficient composting. Allowing the organic material to become anaerobic (compacted) will slow the composting process.
In the composting process temperatures in the compost stack rise and can reach 70OC to 80OC as a result of the activity of the micro-organisms breaking down the organic material. Above 80OC micro-organisms die and chemical reactions take over. This chemical heating can continue to raise the temperature of the organic material until it reaches about 150OC at which point ignition can occur. It is important to note that both the biological and chemical oxidation processes require oxygen to proliferate. Progress is extremely slow under low oxygen (anaerobic) conditions.
Back to the spontaneous combustion sawdust pile court case. In this case the Expert for the Plaintiff used the example of silage production, likening the heat build-up in silage to spontaneous combustion. From the previous discussion a number of points arise. The first is that maize used for silage is green and thus contains a high proportion of nitrogen that is required by the micro-organisms to break down this organic material. The organic material is also moist which fulfils the moisture requirement. However, silage is compacted thus resulting in anaerobic conditions. The silage will simply not burst into flame!
Further issues that mitigated against spontaneous combustion in the sawdust on the Defendant’s property were that the sawdust was spread and compacted i.e. this would have limited the oxygen available to the micro-organisms responsible for composting this organic material. The sawdust pile in question was merely one meter deep and any heat build-up would have been rapidly dissipated. Finally, had there been any combustion in the sawdust pile a source of fine ash would have marked the site of ignition. No such evidence was found.
Sawdust waste – like this – is highly unlikely to spontaneously burst into flames due to heat build-up as the rate of decomposition is too slow!
Conclusion Spontaneous combustion will not occur in sawdust. The primary reason being the C:N ration of this organic material. Sawdust fires will invariably be the result of fire from the outside entering the sawdust pile - as was reported in the Richmond case.
The result of the trial was a finding in favour of the Defendant. Spontaneous combustion was ruled out as the origin of the fire, and honey hunting was identified as the source. This activity had set a stump alight which later - under extreme weather conditions - ignited grass on the edge of the sawdust pile. Despite attempts by the Defendant’s team to put the fire out, it swept across the sawdust pile as well as the firebreak around the sawdust pile into a gum compartment and on into the Plaintiff’s property.
