Plants to root out hazards of landmines

Scientists in Liverpool, UK, are planning to root out unexploded landmines using nothing more than grass.

Plant biologists believe the roots of certain grasses can be enhanced using microbes to the point that they could render below ground landmines harmless.

Dr Richard Webster, at Liverpool John Moores University, who secured funding for a proof of concept from the government’s Advanced Research and Invention Agency, said: “We aim to create a novel way to disrupt landmines and provide a sustainable means to remediate damaged land and restore it for civil use.” 

More than 5,000 casualties are killed or maimed by out-of-conflict landmines and unexploded ordnance each year, three-quarters of them civilians, including more than 1,000 children. 

In conflict mines are frequently cleared by mine plows or blast waves, while humanitarian demining -  removing devices to make the land safe for human use - requires trained dogs, rats, detectors and then mechanical devices such as flails and excavators to clear them. 

Powerful and aggressive

The revolutionary approach would see plant biologically repurposed using microbes to reprogram the roots to be highly aggressive, grow around the buried mines and destroy or disable them. 

The target plant is Miscanthus - a perennial - that has roots powerful and aggressive enough to penetrate plastics that could be enhanced with specific microbes to pierce stronger casings. 

Miscanthus is widely used for biomass production. It grows three metres tall, and spreads via underground stems called rhizomes, which grow horizontally and produce new shoots and roots. This allows the plant to rapidly colonise new areas effectively and thrive in diverse soil conditions. 

“It creates a thick matt under the ground of quite aggressive roots and our proposal is that these traits be optimised using genotype selection and the addition of certain microbial inoculants," explained Dr Webster of the School of Biological and Environmental Sciences.

Current detection methods, such as metal detectors and sniffer dogs, rats, are costly, time-intensive, and sometimes ineffective against modern plastic landmines. Land mines are commonly constructed of PVE and polyethylene, which while hard to detect is weak. 

Deactivate?

Dr Webster, who is conducting the research with colleague Dr Awty-Carroll, added: “Our hypothesis is that both root types will penetrate the mine casing, and that this will lead to either detonation or deactivation of the device.” 

The ongoing conflict in Ukraine has created approximately 174,000 km2 or nearly 29% of its territory affected by landmines, while mine clearance is still ongoing in Croatia, 28 years since it started. 

Previous studies have explored using plants as indirect indicators of mine presence but no-one has yet attempted to actively use plants to disable or neutralise mines.