themax
When the Aggie flowers are finished, you should cut the flower heads off to stop the seed from spreading. They ARE listed as a Weed in some areas. The flowers should be deadheaded particularly if near bushland areas. You don't need them anyway, they clump easily for division if you need more plants.
Yep. Make sure you wear gloves. I once did a few with bare hands, turns out the stalks have an unpleasant sap. No problem just brushing past though.