Legal Question in Real Estate Law in California

Self-help to get rid of trespasses is generally not "legal," the law preferring that the complaining party obtain the agreement of a court and an order directing the trespasser to stop and often ordering money damages for the trespass. However, there are some exceptions, such as the right to trim tree limbs and roots back to the property line, if done properly. There needs to be a balance between petty lawsuits, on the one hand, and neighbors taking matters into their own hands on the other. I would recommend a negotiation, perhaps based upon results of a new survey, if location of the property line is contested. If negotiations fail, you might have to file suit for trespass. I don't think it'd ever be proper to just uproot and cap off a sprinkler line.