My neighbor put in a sprinkling system, and part of it resides on my property. What do i do?

u should be happy he is watering your plants

Tell him to move the sprinklers.

Send him a letter asking him to remove the system from your property. But you had better make sure where the property line is before you do it. If he removes it and it turns out it was not on your property then he can go after you for the expense of taking it out and putting it back in.

Whether there is a fence or not matters not.. the way I would look at it is, I don't have to use my water to water that part of my property. Thanks, neighbor for spending your money to water my lawn.

I would be concerned. He has made a capital improvement (spent money to improve) a portion of land. If that improvement is allowed to remain, it could possibly cloud title rights to that part in the future. I would make sure I knew the actual property line, then ask him to remove the sprinklers from my land.

request he remove it.

You want to know if his sprinkler heads under your dirt create an easement, eventually giving neighbor that property, right? Good question, but would be covered by your state law. You also need to learn who would be responsible if somebody tripped on it and wanted medical care paid for. Call your homeowners insurance for that one. They can sign a release (can't think what it's called at the moment) that says they won't claim the improved land to avoid having to remove the sprinklers.