Three summers or so ago, I'd just finished one off in the front yard when wifey came out and said there was an angry rattler all coiled and hissing in the back....given it's location under a dwarf citrus, I couldn't get a good whack, so ended up calling Animal Control.
The guy showed up and as I was showing him the filleted snake in the front, he started in with the "rattlesnakes are our friends" PC crap......then we got out back, and he took one look and said, "Shit! That's a Mojave! If you ever see another, kill it!!"
Mojaves are reportedly 20 times more venemous than Diamondbacks, and are very aggressive -- and the scary thing is they're known to NOT rattle before striking.)
Diamondbacks are just like Mojaves, except they're not as poisonous or aggressive.