Information – Weed Management

Electrothermal Weeding Demonstration Project

Disclaimer, copyright and licensing

The BHU Future Farming Centre is running a project to develop an electrothermal demonstration weeder for pasture and cropping weeds.

April 2018 update

The AGMARDT application was successful, though at a reduced level of funding, but, sufficient for the project to proceed.  The initial stages of the project are now underway.

March 2018 update

Enough farmers and growers have committed to the project, that an application to AGMARDT is being written with the deadline for Monday 5 March.

Feb 2018 project update

As of 13 Feb, I have emailed all the people who have expressed an interest in the project to date.  I am gathering information on those that want to join and contribute, particularly, those interested in having a demonstration in their geographical area, e.g., possible locations include Southland, Canterbury plains,  Marlborough, South Wairarapa, Hawkes Bay, Waikato and Northland.

The aim will be to have a field day at each location to demonstrate the machine.  This will include detailed use and safety training for those farmers/growers wishing to test the machine themselves.  Then the aim is to leave the machine for one to two weeks with the trained farmers to test it on a wider range of weeds and farms than is be possible at a fielday.  They can then briefly write up their findings, along with before and after photos, that will be collected into a case study report.


Electrothermal weeders are a ‘back to the future’ technology that has been widely researched in the past, especially in the 1980s, but failed to gain traction due to the dominance of herbicides.  Electrothermal is now back, with one of the key researchers from the 1980s, Dr Mike Diprose, coming out of retirement to bring it back to the market, though the start-up company Ubiqutek ( The resurgence of electrothermal is hugely important because electrothermal is the only non-chemical weed control technology that has a systemic weed kill effect, i.e., its as close to a non-chemical glyphosate (Roundup) as is ever likely to exist.  With glyphosate resistance growing exponentially, along with other herbicides, and a growing demand for non-chemical weed control technologies, that electrothermal is back is big news.  For more information on electrothermal please see the FFC Bulletin article

While Ubiqutek are putting electrothermal weeders back on the market the first machines are ‘only’ hand held weeders aimed at the urban weed control market, e.g., councils, and their contractors.  With their current limited personnel and financial resources it will be some years before machines aimed at agriculture and horticulture are produced.  The FFC project therefore aims to accelerate the design and demonstration of electrothermal machines for commercial producers.  This webpage aims to explain what the project is about and garner support.

In any normal situation, Ubiqutek and their NZ distributor Hotgrass ( as the owners / suppliers of the weeders would be developing field weeders themselves, however, not only are both very small business start-ups with limited resources, they also lack expertise in what is required of farmers and growers from field machines especially for the different sectors, e.g., pasture, cropping, viticulture and other permanant crops, and therefore how to design them.  The aim of the project is therefore to not only accelerate the development of a field weeder but also ensure that NZ farmers & growers can get weeders designed to meet their needs.

Clearly Ubiqutek and Hotgrass also stand to benefit from this project, and, they have therefore agreed to contribute to it as well.  Ubiqutek have agreed to contribute:

  • Design and specification of 50Hz transformer with variable voltages
  • UK build of transformer and shipping to New Zealand
  • Build costs for 50Hz transformer
  • Remote support during integration of 50Hz transformer with mechanical platform
  • Supply of samples of next generation modules
  • Redesign of next generation modules for higher voltages (if required)
  • Remote support during integration of next generation modules with mechanical platforms

Hotgrass will contribute

  • Construction of electrical components in NZ
  • Contribution financially of up to $20,000 towards the project
  • Development and delivery of a training package for operators
  • Eventual manufacturing of field machines (via third party)
  • Sales and marketing of the product

The project timeline and outline is:

(1) To get a list of producers interested in the project together by the middle of February.

(2) Once the level of interest has been determined, then, a project plan with costings will be drawn up, and, the amount of funding required from farmers & growers will be determined.  I’m hoping that this will be around $500 to $1,000 depending on how many people are interested.  Only then will producers be asked to commit to the project.  Two amounts will be proposed, one, based on securing AGMARDT funding (see below) and the higher one other should funding not be secured.

(3) A funding application will be made to AGMARDT (deadline 6 March) to leverage the cash contributions from producers.  The current AGMARDT board are really keen on cutting edge / slightly risky projects, and this project should be right in the sweet spot.  The Future Farming Centre has also had two other projects recently funded by AGMARDT, including soil thermal weeding, so, it has a good track record.

(4) The demo machine will be built over winter, ready for demonstrations during the following spring and summer.  Demonstrations will be held around the country so that all the producers who have contributed to the project can see the machine in action and what it can do.

(5) After the machine has been demonstrated and designs finalised, Ubiqutek and Hotgrass will then be in a position to manufacture and supply machines.

The reason the weeder is called a demonstrator, is because there was a very substantial amount of research done and commercial machines built and used in the 1980s.  This included in field crops, and even a machine that killed 20 foot high scrub – see for photos.  Electrothermal has therefore already been shown to achieve a systemic weed kill on a wide range of plants and production scenarios, so, no actual research is required.  The project is therefore focused on designing the application machinery for the different sectors, and then demonstrating that farmers and growers like yourself, on real weeds on real farms, to give you confidence that electrothermal will work for your farming system and what its value could be.

So, please let me know if you are interested in continuing to be involved with the project – no financial commitment is required at this time.  If so please email me at and I’ll put you on the email list.

And, I need help to spread the word about this project, so please let anyone else you think would be interested know about the project – e.g., send them a link to this page.

And finally, Hotgrass, is doing a series of demonstrations around the country which you may be interested in attending – see this webpage for dates, locations etc., and while the demos will be of the handheld machine, they can still clearly demonstrate the potential of electrothermal.

Many thanks

Charles ‘Merf’ Merfield

Head of the BHU Future Farming Centre