By Sam Roberts
It was Professor Noel Sharkey of Sheffield University who, during the long-running and highly acclaimed BBC show ‘Robot Wars’ stated the contestants would be judged on “style, control, damage and aggression” – but how about conservation?
Ok, so this wasn’t a caged arena in an old foundry, in fact it was about as far from that scenario as possible – a chalk downland nature reserve in the heart of West Sussex - but the caterpillar tracks, impressive weaponry, and remote controlled nature of what confronted me was certainly reminiscent of the garden shed versions of the terminator touted by hopeful entrants to this fantastic bit of telly.
This was the latest tool in habitat management being trialled by the Trust – a robotic tractor mower, capable of cutting scrub on slopes of up to 60 degrees. As it drove off the trailer, and down the steep slopes of Levin Down, it instantly impressed the inner child and Robot Wars fan of my past – manoeuvring effortlessly over the undulations, whilst the large flail cutter at the front mowed down the tough brambles, hawthorn and blackthorn so prevalent when left to its own devices. Move over Sgt Bash, Sgt BRASH is in town!
But why employ such futuristic tools? Well, these slopes can be steep, walking up them is tough, so working to clear scrub using traditional tools or brush cutters is just unsafe, let alone cumbersome and hard on the legs. That’s where the mower comes in, not only can it handle these slopes, but it’s remote controlled so no danger to the operator unlike traditional sit-on tractors.
And why clear the scrub in the first place? Well chalk grassland is a rare habitat, comprising of more than 50 species of wildflower in one square metre – this can easily be swamped by invasive plants – so we need to manage it by cutting it back. Levin Down also has a particularly important habitat of chalk heath – where you find acid loving plants such as heather growing on a thin layer of wind-blown soil that sits on top of the chalk – this mixture of different types of plant is quite a rarity so is well-worth protecting. We still leave areas of scrub untouched for sheltering birds and insects, but too much can drown out these important and less-common species.
After a day’s mowing, you could certainly see the difference, with a large area of what was near thicket now an open area – perfect to allow the grazing cattle to come in and finish what was left, as well as get a chance to eat any new shoots that might grow back in spring. A perfect start to some grassland restoration, and a good test of the tractor’s abilities – style =10, control = 10, damage [to scrub] = 10 and aggression? Well, the friendly South Downs National Park rangers helping were anything but aggressive – sorry Professor Sharkey.
Watch the robotic tractor in action
Thanks to the South Downs National Park Authority for their loan of this equipment, and to their rangers for the help with this work.