Do you feed the BG? If not then set up a feeding program to feed BG helping to get more young out there. Also are your 10-13” LMB thin ? If between the crappie and LMB are consuming the BG before they reach a size to benefit growth in LMB. In my pond there are too many small LMB that are eating the size that benefits their growth . The large LMB are eating the larger BCP. When you rid of pond weed IMHO you stop the survival of BG cause they get eaten by the numerous LMB compounding the problem. Instead of wiping out
the
BCP might try putting out structure and feeding high protein feed for the BG and maybe adding more BG