I'm having a 6 year old clump of black bamboo removed as it wasn't planted with a root barrier. There are a several large culms (20 feet high) which have come up about 10 feet away from the mother clump. These new culms are close to the roots of an old forsythia and are going to be difficult to remove. If the mother clump is removed, will the offshoot runners die off, or form a new clump? As lovely as it is, I want to be rid of it all.
If those satellite clumps are well established, and at least a year old, they will survive. But you can deal with them without digging them out by cutting the clums right to the ground, and then keeping a watchful eye on the area for any new emerging shoots. As soon as those appear, cut them off. The idea is to not allow the clumps to photosynthesise, thereby, depleting the rhizome mass of nutrient supplies and reserves.
