There's a flat, spreading weed with thousands of prickles in tiny clusters
that you pick up in bare feet and once in your feet the tiny prickles are
indistinguishable from those of bindii. Its leaves are dark green and very
glossy, and it's distinctive in having one central turnip-like tuber: if
you can dig up the tuber, the whole plant lifts off the ground with it.
The seeds/prickles are widely distributed by vehicle tyres and shoes,
meaning the most likely place to find it is in the lawn alongside the car
tracks and on the edge of public footpaths. It is hardy and thrives as a
thick mat cover in infertile, compacted sandy soils. What is its name?

Zero doesn't have much effect on it; is it susceptible to any other
relatively safe weedicide?
--
John Savage (my news address is not valid for email)