For those who might be interested in knowing what happened to our struggle
with black ground squirrels, we have a good news - sort of.
After trying everything (fox urine, ultra-sonic underground noise maker,
and trap), we decided (or accepted defeat) to try to live with them.
We started to feed to them.
For some reason, they were unseen for a while, but now they are back.
We don't see them as often or as many as we used to.
We bought a corn feeder that can supposedly entertain both squirrels and us.
Think of it as a metal four-wing windmill.
At the end of each "wing," you can attach corn-on-the-cob.
So when a squirrel gets on the top of the corn, it spins around.
I haven't seen the squirrels in action, but my wife did.
She must have enjoyed it, as she told to me replenish the corn. :-)
Hopefully, those super-intelligent squirrels got the message,
and start reciprocating our goodwill by staying away from the flowers. :-)