1,000 caterpillars let loose on Port Meadow in Oxford

Volunteers battled for years to remove the noxious plant which stands about 2ft high sporting bright yellow flowers.

All sorts of ideas were put forward to eradicate or at least control the weed without any great success.

One ingenious idea in 1965 was to put more than 1,000 cinnabar caterpillars on the meadow.

According to experts at the Buckinghamshire, Berkshire and Oxfordshire Naturalists’ Trust, the only food they liked was ragwort.

Nearby allotment holders objected, arguing that the caterpillars would eat their cabbages and other vegetables, but were assured they would eat only ragwort.

Sadly, the experiment failed when the caterpillars grew fat on the weed, turned into chrysalises, became butterflies and flew away.

The experts scoured the meadow in vain for any sign of the insects, and the ragwort shot up next summer just as hardy.

One strain of the weed was called Oxford ragwort, which came originally from the slopes of Mount Etna in Sicily.

It was brought to the Oxford Botanic Garden between 1670 and 1680 and the seeds apparently escaped over the garden wall to the outside world.

Former Botanic Garden superintendent Ken Burras told the Oxford Mail: “Once it had escaped, dispersed by its silky parachute-like wings, the seed was whisked through the city.”

Then, with the coming of the railways, the seeds were transported around the country.

At first, Oxford ragwort, with yellow flowers and 2ft high very similar to the original plant, could only be seen growing alongside railway tracks, but it later spread almost everywhere.

One expert said: “It particularly likes building sites and stone crevices.”

Roger Clarke, of the Naturalists’ Trust, watched by the Sheriff of Oxford, Olive Gibbs, puts caterpillars on the ragwort in 1965 (Image: Oxford Mail)

The most effective way of getting rid of ragwort was to pull it up by its roots and burn it, a job which could be back breaking.

The idea of spraying Port Meadow to kill it was ruled out for fears of killing other flora.

By 1980, another problem was rearing its head – thistles were taking over a large part of the meadow.

Oxford City Council’s answer was to use weedkiller, but that brought immediate protests from Wolvercote Commoners and eminent scientists.

They claimed that cutting the thistles would have “huge advantages” by being cheaper and less destructive.

Other voices were raised in defence of the meadow’s colony of goldfinches. It was claimed they were likely to be left homeless if all the thistles were removed.

With so many different views, beleaguered council officials wondered which way to turn next!

The top picture shows Fred Archer, a freeman of Oxford, examining the ragwort on Port Meadow in 1975 while in the lower picture, Roger Clarke, of the Naturalists’ Trust, watched by the Sheriff of Oxford, Olive Gibbs, puts caterpillars on the ragwort in 1965.