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Professor works for a chemical-free sustainable future

Bo Melander takes on the role of professor of weed science at the Department of Agroecology, Aarhus University. He has spent decades studying how to maintain a productive and sustainable agriculture without resorting to pesticides. From battling couch grass on his parents' property on Langeland as a child to his current work on non-chemical weed control, sustainable approaches to agriculture have been his focus.

[Translate to English:] Professor Bo Melander Photo: Camilla Brodam Galacho

Bo Melander's interest in agriculture and sustainability started during his childhood on the Danish island Langeland, where his father worked as an agricultural consultant. At the age of seven, Bo Melander accompanied his father on visits to Danish farmers. 

“It was here I developed an interest in agriculture. At that time, there were significant issues with weeds on Langeland, particularly with wild oat, which was the main focus,” Bo Melander explains. 

As a consultant, Bo Melander's father advised farmers on how to best combat weeds. Since there weren't many pesticides available at that time, the focus was on non-chemical weed control. This is also something the new professor has practical experience with from his parents' property. 

“There was couch grass in large quantities, and when I came home from school, I worked in the field with the harrow to see if I could get rid of the weed,” he says. 

Even after hauling wagonloads of rhizomes away from his parents' fields, Bo Melander did not lose his enthusiasm for agriculture and weed control. He chose agronomy as his path, and it would turn out to be the key to his passion for sustainable agricultural practices. 

Organic cultivation and non-chemical weed control 

In 1988, Bo Melander was employed at Flakkebjerg Research Station, where he began his career focusing on experiments with weed control for species like blackgrass, loose silky-bent grass, and couch grass. 

“The experiments we conducted were part of the government's efforts to reduce nitrogen leaching and limit the use of synthetic pesticides,” he explains. 

Bo Melander gradually worked his way up in the research world, even though permanent positions were not guaranteed at that time. He had to seek and secure funding for his research projects himself, but his passion and commitment remained unwavering. 

By 1994, Bo Melander had shifted his focus to organic farming and non-chemical weed control. The government at that time had a goal to promote organic cultivation and reduce pesticide use, bringing significant attention to his research. Consequently, he became an integral part of a research team working to develop methods for weed control without the use of chemical agents. 

Robots and strip steaming 

Throughout his career, Bo Melander has been involved in developing innovative technologies, including robots that mechanically combat weeds in various crops. 

“In collaboration with Frank Poulsen Engineering, we have developed robots that automatically remove weeds between sugar beets. This technology is possible thanks to artificial intelligence that detects beets in different situations and controls a weeding devise for automatic weed removal. I have been involved in this development from the very beginning,” he explains. 

Bo Melander is the Gyro Gearloose of weed control. For example, weeds can be combated by steaming the entire soil surface down to a depth of 15 cm, but Bo Melander had an idea.  

“We worked with a concept where we only steamed in the rows where vegetables or crops were sown. It is relevant because when you steam in the row where the crop is going to grow, you kill many of the weed seeds that could otherwise cause weed problems in the crop later. You could almost say that you sterilise the row that needs to be cultivated,” he explains, adding, “However, it's not a method used anymore. But it was widely used for a period.” 

Love for plants and nature 

In addition to his work as a researcher, Bo Melander is a botanist at heart. He has a great passion for wild plants and is active in the Danish Botanical Society, where he shares his knowledge of plants and nature with the public and leads tours and excursions. 

Botany will also play a role in Bo Melander's future work as a professor. 

“My knowledge of botany and plant communities is something I want to bring into play in the coming years in connection with the increased focus on biodiversity. I want to work on what we can do for agriculture, i.e., the cultivated surface, to contribute to increased biodiversity. Over 60% of Denmark's area is cultivated. It goes without saying that if Denmark is to contribute to an improvement in biodiversity, it is not enough just to look at natural areas,” he says. 

However, he points out that it's not straightforward; agriculture must produce enough while providing food for insects, birds, etc. 

“We just have to recognise eller acknowledge that agriculture must help. This could be done, for example, by having more living fences and various small biotopes here and there. It's not something that can be solved just by snapping one’s fingers, but it's something I will spend time and effort on,” he says. 

The future of weed control 

Bo Melander continues his work in the field of non-chemical weed control, contributing to the development of methods and technologies that help farmers reduce pesticide use and promote sustainable agricultural practices. He has been a key player in Danish agricultural research and has played a crucial role in the national and international efforts to find solutions to weed problems in agriculture. 

He has, among other things, been the chairman of the European working group on non-chemical weed control for 12 years, contributing to shaping the future of weed control across continents. 

From the fields of his childhood on Langeland, where he fought weeds with his father, to his current position as a pioneer in non-chemical weed control, sustainable approaches to agriculture have been his cause. What the future holds, even a professor of weed science cannot predict, but: 

“I will continue to work on sustainable solutions for agriculture. The need for non-chemical weed control is increasing as more pesticides are banned or weed plants become resistant to them. Technology is with us, and I will continue to collaborate with engineers in the future so that we can develop new robots that, through machine learning and AI technology, can help us combat weeds in a sustainable and non-harmful way in the future,” he concludes. 

Aarhus University has appointed Bo Melander as a professor of weed science, effective from November 1, 2023. He will give his inaugural lecture on December 13, 2023. Further details and invitations will follow. 

More information 

Contact: Professor Bo Melander, Department of Agroecology, Aarhus University. Phone: +45 22283393 or e-mail: bo.melander@agro.au.dk