Meet the robot that maps weeds on farm for National Trust

By Sam Russell, PA

A National Trust estate has brought in a robot to map the location of weeds in a bid to cut chemical use and improve environmental performance.

It will allow farmers to apply herbicides solely to areas where there are weeds rather than spraying large areas.

Two further robots are in development, one to zap weeds with an electrical charge and the other for precision planting.

It is hoped that the zapping robot will remove the need to use chemical weedkillers, which harm biodiversity.

The robot called Tom being used to map weeds at a National Trust estate (Sam Russell/PA)

Callum Weir, farm manager at Wimpole Estate in Cambridgeshire, said the weed-mapping robot called Tom helps improve efficiency and benefit the environment.

The weed-zapping robot and the planting robot, both in earlier stages of development, will be called Dick and Harry.

The 1,500 acre (600 hectare) organic farm at Wimpole grows wheat, rye, oats and barley.

“The beauty of the robot (Tom) is that it gives me absolute precision,” Mr Weir said.

“If I were to go and walk a field, I would walk a W shape in a field and be able to see two metres in front of me.

“This robot can map every centimetre of the field and give me recommendations for different parts of the field.

“Instead of me looking at applications from a field scale, I will go to a metre-squared scale.

“That means I can be much more precise in the applications that I apply, the operations that I do, saving fuel, saving fertiliser and increasing biodiversity.”

The robot is fitted with two downward-facing cameras to monitor what is in the field, has sensors to detect obstacles as it trundles around and transmits data to be stitched together into a map by software.

It is powered by electricity, reducing emissions, and has a four-hour battery life.

It can map 50 acres (20 hectares) per day, according to the National Trust.

The 150kg (23 stone 8lbs) prototype compacts the soil far less than a traditional seven-tonne tractor does, Mr Weir said.

The National Trust pays Salisbury-based Small Robot Company for the service, and the robot visits four times per growing season.

Wimpole, which Mr Weir said is the National Trust’s only in-house farm, is demonstrating the technology to some of its tenant farmers, of which there are 1,700.

“We are really keen at this quite important time of biodiversity decline, climate change mitigation and political uncertainty around farming that we support our tenants to make sure they have sustainable livelihoods,” Mr Weir said.

Sam Watson-Jones, co-founder of the Small Robot Company, said: “Farmers are the same as any other people in that you have a group of early adopters.”

He said the idea for the technology came in 2016 and had developed to its current stage with the help of crowdfunding and government grants.

The firm is working with the company Rootwave to develop a robot that can zap individual weeds with an electrical charge, removing the need for chemicals.

Rob Macklin, the National Trust’s head of farming and soils, said: “Technology needs to play a big part in solving many of the issues we currently face in farming – particularly improving soil health and carbon sequestration, reducing our reliance on fossil fuel power and fertilisers and avoiding the adverse impacts of synthetic chemicals on the environment.

“We want to encourage nature-friendly farming practices, and we have to lead by example and embrace innovations.”

It is hoped Tom and Dick will be commercially available in 2021.