Tips for stopping incessant barking

My ACD mix has 100% cattle dog brain and loves to herd her dog housemates and people. The problem is that she tends to bark incessantly the entire time she's chasing them or following them. She also barks incessantly at feeding time or any time she's extremely excited, such as getting ready for going to the park or walking.

Otherwise her barking habits are normal for the breed, the occasional alert bark or tantrum grumbles when she doesn't get her way. She's fairly quiet when left alone in the house and settles.

We've tried using a 'hush' command and reinforcing it with treats as a reward when she stops barking, we've tried time out to give her a chance to calm down, we've tried stopping our activity and ignoring her when she barks until she's quiet before continuing. The problem is that she'll stop for a moment and then immediately resume barking like mad. She's a highly trainable dog and does seem to want to please me as she easily learned commands for sitting, has good recall, learned to jump up onto surfaces on command, wait at doorways until released, etc. We've considered getting a collar that will play a beep or vibrate when she barks so that we can interrupt the barking and immediately praise as we're not certain that we're being quick enough to help her connect the dots as she seems to think what we want is her to sit down and stop wiggling as she'll do that but then bark at us.

Any recommendations? I don't expect her to never bark, I just want to be able to give her a command to stop a chain of barking or to indicate to her that it's not time for that.