The pigs that kept the Japanese knotweed and giant hogweed in check on Zernike Campus these past few years will not be returning this spring.
The invasive weeds push out native plants with more ecological value, and hogweed leaves nasty burns if people touch it. The pigs love eating the plants, often including the roots.
Eliminate
But the weeds keep returning and the university wants to eliminate them once and for all, says spokesperson Elies Wempe-Kouwenhoven. ‘The pigs control the plants, but they can’t combat them.’
The UG is in talks with Hanze and the municipality about how to do this, as they are all owners of the land on Zernike. ‘You can lay down plastic, you can add glyphosate in the stems of the knotweed: there all sorts of things you can use’, says Wempe-Kouwenhoven.
Showcase
Dick Jager, manager of integrated sustainability, isn’t happy about the decision. ‘It’s a real pity’, he says. Jager often showed off the pigs to universities abroad as a sustainable way of improving biodiversity at the university. ‘And now they want to stop this. Why? Because it’s also a showcase.’
No decision has been made yet as to how the weeds will now be combated, but action will have to be taken in the coming weeks, says Wempe-Kouwenhoven. ‘It is spring now, so they are growing like mad.’
Not long enough
Pig owner Willem Hempen says the UG did not keep up the trial with his pigs long enough. ‘The pigs have been working there for three years, but they need four to five years to control those plants.’
‘To me, this is negative publicity: now it seems like the pigs aren’t a good solution.’ That is absolutely untrue, he argues. ‘In all the places where the pigs went for the full five years, the knotweed has disappeared 100 percent.’
That’s why he was so surprised when he heard that his animals were no longer going to be used. The pigs are a sustainable and nature-friendly way to control invasive non-native plants once and for all, he argues. He thinks it’s a shame and hopes they can still help in the fight against weeds at Zernike.
CORRECTION: Initially, the UG reported that they were considering pesticides as an option to control the hogweed and Japanese knotweed. After the uproar this caused, the UG reconsidered. Glyphosate will not be used, a spokesperson said. The article has therefore been updated.