It’s very difficult to get crows to move along, especially of they find your backyard to be inviting. What I do is to try to make my yard unappealing to crows. I have removed large sources of water and replaced them with small cups of water - large enough for finches and not much else. I play my hawk/birds-of-prey loop first thing in the morning and at dusk. I also clean up debris that can be used as nesting material - I have even replaced all shredded mulch with wood nuggets. Crows are very intelligent, and will stick around and try to outsmart you. Keep a close eye on your garden and try to figure out what might be attracting them, and remove it if you can. Also consider the time of day when automatic sprinklers come on, as they may be attracted to the water. I’ve begun watering at 4 a.m., before the sun rises.