Yes, I've used BT a lot over the years. It's expensive and ineffective if it hasn't been stored properly. Dead BT just doesn't work. It DOES work, but it's not an instant result.
I found when I had good live BT that it didn't start working until mid to late summer after the initial application. It also lasts through multiple years. I've usually found the 2nd year after an application had a much more effective rate of kill and started early in the season. After that it starts tapering off. I think the effects lasted through year #5 once, but it probably would have been better if new BT had been spread about on year #4. A reasonably wet season seems to also help it do the job.
It's gratifying to see grasshopper bodies turning dark and lethargic and then being cannibalized, though. If it hasn't been stored properly, I think Nosema locustae is killed rather quickly and then you wait and have just wasted time and money. It's not possible to know what the storage conditions have been from the source to you. If you see it in the local feedstore just sitting out on a shelf with feed, don't bother.
