Yes, they'd be fine. I don't think anyone has ever managed to kill a Stella d'Oro. They're really a work horse plant. I'd opt for a sharp spade since you will have to dig down (at least 6 inches) and under a bit. I'm just not sure a sharp knife would slice through the clumps so a piece could be lifted, but a pruning saw would work.

Stellas grow so quickly, in a couple of seasons you'd have your own good sized clump to divide. I have to divide mine every two years - they get the size of a bushel basket.

As to whether or not these mown down plants are for the taking, I can't say - perhaps the block has a new not so skilled maintenance person or the planting scheme is to be changed anyway.

Thank you!