It WAS once a plant of the seashore, thriving in salty soil, but now Danish Scurvy-grass is spreading with winter road salt, creating the perfect conditions for the plant to grow on the verges of roads and motorways.
It was once deemed a very useful plant. When Irish sailors returned home from a long sea journey, they went to the seashore to harvest the Vitamin C-rich plant that helped ward off scurvy.
According to Zoe Devlin's Wildflowers of Ireland – A Personal Record, another factor is that seeds of the plant (Irish name: Carran creige) may be picked up by foreign trucks entering Ireland through coastal ports and then distributed throughout the country.
Trucks and cars travelling at speed on roads leave a wind vortex in their wake on which seeds can be carried long distances.
While Danish Scurvy-grass is not a problem, there are some plants, especially noxious weeds like ragwort, which are problematic. Ragwort poisons livestock – even if fed to them in the form of hay or silage.
For years, the National Roads Authority (NRA) has paid a special maintenance grant to local authorities to deal with the problem of ragwort and other noxious weeds.
That will now change, with the NRA taking over responsibility for maintenance on the motorway network, and contracting the work out directly to private companies in the coming weeks after a tender process.
Road users noticed that much of the grass on motorways in the last few weeks was left to grow, though some cutting did take place in the last week or so.
According to Vincent O'Malley, environmental manager of the NRA, the protection of the roads environment is a real science.
"What we want to do is to create more environmentally favourable landscapes. When you do put a road into a green-field site, there is an impact. We want to enhance the environmental impact, promote biodiversity and produce landscaping which is sustainable into the future.
"That means producing underpasses for mammals, building mammal defensive fences so they don't get on to the roads and get killed, and protecting the habitats. There is a whole ecological lifestyle taking place under these roads," he said.
There are other plants besides ragwort that can cause problems, including non-native invasive plants like Japanese knotweed, buddleia and montbretia. They can choke other plants if not properly controlled.