Scottish Thistles

The other day, fellow blipper Apothecary7, blipped a thistle and explained why the spear thistle has become a Scottish emblem. 
https://www.blipfoto.com/entry/3391083096320247185 
When I see one, the Scots phrase, Wha daur meddle wi me, always springs into my mind, but I had no idea why. I now discover that is the the motto of the Scotland's Order of the Thistle and of some Scottish army regiments. My education was not wasted on me after all.