Report on New Weed Control Technologies

Hort Innovation, Australia’s representative body for their horticulture industry, have released a new report examining up and coming weed control technologies.

Benefits and drawbacks of each technology are noted, and each is rated out of 5 for Soil Wealth (impact on soil health, biology etc) and ICP (minimising risks to environment, crop, growers and reducing chemical use).

We’re thrilled to announce that our Satusteam technology topped the charts with full 5/5 ratings for both criteria!
The other technologies are well worth investigating as well, as there is no one-size-fits-all solution to reducing chemical use in horticulture.

Check out the other alternatives and full report HERE.

Considerations and Advantages when Using Satusteam©

With the increasing knowledge about the health effects of repeated exposure to glyphosate, landcare groups are opting for a range of alternatives.

‘Steam’ has proven to be a valuable tool, particularly for some invasive species like Mother of Millions and Tiger Pear, but before you spend your hard fought for grant money, consider some of the features that will make huge differences in your productivity.

There is more detail to follow, but first, let’s destroy a myth about steam weed control. Steam, the vapour seen rising from applicator heads, is the minute vapour droplets have no lethal temperature associated with it. It’s the large coalesced droplets of boiling water that are the treatment fluid. This fluid is a mixture of saturated steam and boiling water, which we call Satusteam©.
It is not generated in a pressure vessel, like a soil steriliser or home heating system, but in a continuous flow hot water heat exchanger. It delivers enough volume, delivered at a 98°-100°C at the weed to explode soft leaved cells on contact. Thermal shock takes just 1/10th of a second.
We have an in-depth article comparing various thermal control methods to Satusteam©, click here to read it.

To arrange a demonstration or find out more, call 0800 112 890.

When fighting weeds with steam – volume matters

In landcare situations, you need serious killing power to fight difficult weeds. Our machines were first developed to treat weeds in municipal areas such as crack and crevices in footpaths and paving. 5 litres a minute works well in that situation, but in landcare and regeneration environments you will want a machine that delivers 10 litres.

Vegetation in soil and mulch grows more vigorously than in the harsh pedestrian environment.

The roots are more established and often the vegetation being controlled may be a ground cover or established grass. A 5L/min machine such as the SW800 can be used but productivity will increase dramatically, as well as your satisfaction level, with double the volume. Our contracting customers, who have their choice of machines, will choose the SW900 for controlling weeds in the soil every time.

The SW900 can be set up with dual reels and have 2 operators, adding to its versatility.

Temperature up close is key

Back in the early 2000s, I learnt a valuable lesson. Hot water of 97°C makes progress/work much slower than using boiling water when the aim is to explode plant cells. Weedtechnics SW machines superheat the water as it passes through the steel pipe inside the burner chamber. Because it is pressurised, the water can be heated up to 115°-120°C without boiling. Pressurisation raises the physical boiling temperature of water to over 300°C. We maintain this pressure through our delivery hose and lance, right up until it passes through our unique nozzle system. What this means is that your superheated water doesn’t flash into saturated steam and boiling water (Satusteam©) until it is within 5cm of the target. There is no time for it to cool in the atmosphere, therefore transferring maximum heat into the target vegetation.

The depressurisation advantages

The Satusteam© system pressurises the water for two reasons. Firstly, it raises the physical boiling point of the water allowing superheating. Secondly, it allows delivery of the super-heated water over any distance up to 100m from the boiler and still delivers Satusteam© at 100°C.

Our patented nozzle system depressurises the superheated water; to give a safe and controlled delivery. The maximum-heat Satusteam coats the vegetation rapidly, which gives you great productivity. Depressurised Satusteam© does not displace mulch, compact soils, inject into desirable roots or damage soil structure. This feature also allows the machines to be used for cleaning of lichen, moss, algae and more without damaging the surface beneath, unlike a high pressure waterblaster (alternatively pressure nozzles can be used with the machines for pressurised cleaning).

Reach and rewind makes work easy

Landcare and revegetation works are rarely in compact areas. So, look for a unit that can deliver the volume and temperature over a long distance. Because of our depressurisation advantage, the Weedtechnics Satusteam© system can deliver Satusteam© at 100°C up to 100m from the boiler. Our standard landcare reels can house 60m of covered hose on a rewind reel. This gives incredible reach and versatility to your work.

Water carrying capacity

We have established that 10L/minute is going to give you the most productivity when dealing with weeds in broad landcare environments.
A 400L water tank will give less than 40 minutes of work. A 1000L tank will give you 90 minutes. Consider the effect on productivity with having a limited water supply.

Variety is the spice of life

Mother of millions, kikuyu, couch, hydrocotyl and similar ground covering vegetation is best treated using a 35cm or 60cm wide covered head.  The covered environment encapsulates the heat ensuring there is the maximum transfer of heat to the plant material. Covered heads also allow application under the foliage of desirable plants without fear of off-target damage.

Tiger pear is best treated using an open head, that can be used to coat the entire above ground portion of the plant. With the same head, tussock grasses are managed well having a good dose of 10L/minute of Satusteam© delivered into their crown. When you are done with the work on site and want to sanitise your vehicle tyres and remove any seed from plant and equipment, you will want to be able to use a pressure nozzle in your Satusteam© weeding machine. Weedtechnics have developed the threaded quick coupling system that allows you to change between nozzles within 90 seconds.

In most cases, following safe work methods, you may not need to turn off the machine or cool it down. This can be followed up with a steam spike injection.

Technical support 

Use of burners and boilers by landcare practitioners is new, so you want to know that there is support just a call away and that they know how to troubleshoot. Weedtechnics have developed this system over the last 20 years and have been using our US made, clean burning, fuel efficient boilers for the past 10 years.

We know intimately how to troubleshoot and have assisted many customers get up and running with phone support, without them having to leave their sites.

 

If you’d like to discuss how we can make the Satusteam© technology work for you, please don’t hesitate to get in touch.

Thanks to our team in Australia for this content.

Go Green on Weed Control

What new service could you offer that would generate referrals and more business?

Consumers are preferring ‘green’, ‘eco’ and ‘organic’ and it’s no longer acceptable for much of the community to see chemicals being sprayed for weed control.

THE FACTS

The public is concerned about safety.
Application of chemical weed killers, according to label, requires restriction of access to treated areas for a number of hours. Failure to restrict access can expose the public to ‘probable carcinogens’.

Glyphosate negatively impacts soil biology.
The most commonly used weed killers are Glyphosate based. Glyphosate is a patented antibiotic and chelator which has been shown to kill soil microbes, bind nutrients and favour pathogens.

Weedkillers threaten habitat, ecosystem & pet health.
Most commonly used weed killers have the potential to contaminate habitats of sensitive populations of endangered species such as frogs, bees and butterflies which are essential to healthy ecosystems.

Stormwater becomes contaminated with herbicides applied to landscapes.
Chemical weed killers translocate easily from paved surfaces, through soil profiles and contaminate ground waters, streams, creeks and estuaries.

These problems have created the next great opportunity for differentiating your business and standing out from the crowd.

Residential Consumers are favouring ‘eco’, organic and bee, child and pet-friendly products.

School and Dog Steam Weeders

Commercial clients want Eco
Companies, councils and schools report to their stakeholders on their eco-initiatives. You can assist them to achieve their eco-outcomes. Offer organic Satusteam weed control from Weedtechnics.

Be a leader
Add Satusteam™ to your tool kit offer as a new service. Weedtechnics has a range of machines to suit your needs. The new SW500E is versatile and easy to use. It plugs into water and power wherever you go; or can be used with a generator. The SW900 is a more serious workhorse. It can run all day with one or two technicians on 60m hoses.

Use SatusteamTM weeding machines to kill weeds in cracks and crevices in driveways, carparks, along fence lines and in gardens. The machine can also clean and sanitise slippery paths, rubber surfaces, artificial grass, play equipment, as well as remove chewing gum and some graffiti.

Sydney Inner West Council has had a SatusteamTM weeding program outside every school and pre-school in Marrickville for many years.

With Weedtechnics SatusteamTM, you can be a step ahead of the rest

36 councils across Australia use Satusteam to weed and clean playgrounds and civic areas. Much of this work is contracted.

Thanks to our team in Australia for this content.

SW900 and Rowtech Video

This is some extraordinary drone footage of a SW900 and Rowtech set up, being operated from the set of a tractor.  The hydraulics were created by the owner of the machine, Weedtechnics can also supply our equivalent Hydro-Boom set up.
This is an organic farm producing Haskap berries, which are native throughout the cool temperate Northern Hemisphere in countries such as Canada.

 

The Science Behind Thermal Weed Control

Well actually “YES IT DOES”, but there is a little more to it than it sounds.

Universally weeds are a hassle for farmers, gardeners, property owners and landscape managers. Hand digging and mulching is the ‘go to’ method I use in my own garden but this can be problematic for commercial crops and public open space. With the wealth of information now in the public domain about the health and environmental issues related to chemical herbicides for killing weeds, there is a major shift to adopting non-toxic weed control methods.

Steam weed control falls under “Thermal Weed Control” category on non-toxic methods. These can be classified into the following Hot Dry and Hot Wet categories.Thermal Weed Control Methods

Hot Dry includes controlling weed with infrared radiation, flame and hot air. They all use propane/ LPG as their heating source.  There are a number of small flame units available which are comparatively portable and are used by home owners, land-care groups and some cities.  There are also larger ones such as HOAF and Sunburst with ride on or tractor versions.
There are some obvious limitations of using a blast of open flame to cook weeds.  Dry leaf litter and grass easily catches alight and the flame melts rubber soft fall in playgrounds and rubber paving, and irrigation lines melt on contact.

My observational experience of using flame is that it doesn’t really penetrate the crown of the plants. It cooks off the top pretty effectively but regrowth from the crown is observed within a few days after treatment.  This leads to having to treat frequently.

Hot Dry Weed Control

Let me explain why this is the case. I remember when I was in science lab at high school and we had Bunsen burners alight. My classmates and I would see how slowly we could pass our fingers through the flame. Despite feeling the heat, we didn’t end up with any blisters.

That is because as we passed our fingers through the flame we were exposed to dry heat and dry heat doesn’t linger. Whilst the temperature of the flame was in the vicinity of 1300° C / 2400° F the heat transfer of hot air and flame is quite slow and air cools as soon as the flame or other radiant heat source moves on, or in the case of our fingers, they moved to cool air.

When using a flame to cook weeds, in order to get better penetration and a consequently longer die back, the flame must be held in place for a period of time long enough for the soil around the root to heat up.  The problem with this is that it increases the chance of fire and damage to the assets you are trying to protect by weeding. I have observed better results in early morning when dew is present or after rain.  For a start its safer, but I also reckon the water boiling on the leaves is retaining the heat for longer and transferring the heat into the leaves more efficiently.

Hand held and push type flaming and radiant heat apparatus can be useful because of their portability but they come with high risk of off target damage.

Of the hot dry methods available flame and radiant heat from ceramics or metal plates heated by flame are the most effective.

Hot Wet methods of weed control include steam, hot water, hot water and insulating foam and saturated steam and boiling water.

Some hot wet methods are regarded as having superior control over weeds than hot dry method.  The reason for this is easily explained by comparing the Bunsen burner at 1300 °C/ 2400 °F to almost boiling water at 95 °C/ 203 °F.  The devastating burns that occur when a cup of freshly brewed tea is spilt onto skin is a perfect example showing how the water transfers heat so effectively and intensifies the damage as it stays on the skin.  Hot oil is even more effective as it doesn’t evaporate and heats to higher temperatures than water. People that work in kitchens learn soon enough that the worst burns are the hot wet oil and water scolds, rather than the more localised burns from touching a hot dry pan or oven rack.

Hot wet methods of weed control enable more rapid transfer of lethal heat into cell structure of weed. In hot wet methods, deeper penetration into the crown of the plants is achieved.  This is where the meristematic cells that are the central growing point of many weeds are.  Most common soft wooded, annual and perennial weeds by their nature are plants that have migrated or been introduced from environments such as grasslands, prairies and open forests.  In their natural environment they are grazed upon by ruminants and occasionally exposed to fire.  They are adapted to growing back from the meristematic cells, the crown of the plant that sits at about or just below soil surface.  They draw on the stored energy of their roots to regenerate new stems, often multiple stems, and a new flush of leaf growth to start the process of replenishing their root system and stored energy. Hot Wet Weed Control

What makes hot wet methods so effective is that they are unlike any process that the weeds are adapted to. The heated fluid penetrates and damages the growing tips, delaying the usual rapid regeneration that is experienced with dry thermal or mechanical cutting methods.

Have you ever hand weeded a garden bed, thinking that you have left the soil weed free, job done, only to have a veritable vegetative carpet of seedling weeds appear after the first moisture?

That’s the seed bank being triggered to life by the warming of the soil, previously shaded from the sun by the weeds you removed, perhaps some exposure to light and certainly some available moisture. So, what I have seen time and time again in weeding with boiling water is that the combination of adding heat and water to the soil surface germinates some species in seed bank. Some species of seeds can’t tolerate the heat and are de-natured, they die and decay in the soil, whilst others love it, as it splits the hard seed coat and allows their first embryonic roots and shoots to emerge. Either way it’s a bonus.  It’s a bonus because we can now deplete the seed bank which means that we can control next year’s weeds this year.

Seed Bank Diagram

I won’t go into the environmental contamination and potential health effects caused by chemical methods of pre-emergent seed bank control, because seriously we can manage the seed bank with just water.  Really, really hot water!

 – Excerpt of an article written by Jeremy Winer

If you still have an itch to learn more, feel free to read Jeremy’s Holistic Vegetation Management Report.  This paper further explores methods of thermal weed control and cites scientific research into weed management practices from around the globe.

Holistic Vegetation Management Report