Danish scurvy grass is a tiny flower which grows in early spring. It thrives in salty soils which would kill off most plants.
Despite the name, it is a native plant. But up to about fifty years ago, it only grew right by the sea. Then, in the 1960s, salt started to be added to the grit spread to keep the roads clear in winter.
This scurvy grass began to spread; first along motorways, then other main roads. It’s so small that it’s inconspicuous, but the chances are that it can now be found growing by any road which is gritted regularly and also has soil near enough to get splashed by the resulting brine.