1) Abounding in prickly plants 2) Tough to handle 
• (a.) Overgrown with thistles; as, thistly ground. • (a.) Fig.: Resembling a thistle or thistles; sharp; pricking.
This'tly adjective 1. Overgrown with thistles; as, thistly ground. 2. Fig.: Resembling a thistle or thistles; sharp; pricking. « In such a world, so thorny, and where none Finds happiness unblighted, or, if found, Without some thistly sorrow at its side.»