Legal Question in Real Estate Law in California

Re: neighbors tree

The law is not on his side. If the limbs overhang your property, that is a trespass. Although the law does not generally favor self-help to correct a trespass, courts condone trimming invasive tree limbs and roots if it is done "in a non-negligent manner" to quote one case. That is usually thought to mean the trimming must not seriously injure the tree nor make it likely to blow over in a windstorm. If you had it trimmed yourself, you would probably not be allowed to recover the cost in court. Whether the leaves and fronds that fall or blow off are also trespassing is less certain; I do not recall any case law and an analysis based on fundamental principles of intentional torts shows arguments could be made either way.

However, the falling and blowing tree debris is certainly a private nuisance, if not a trespass. The legal concept is somewhat different from trespass, but I think you are a reasonably clear winner here. Something is a private nuisance when it constitutes an unreasonable interference with a property owner's right to enjoyment and use of his property. Remedies for private nuisance can include money damages and an injunction.

I recommend further attempts at a negotiated settlement before plunging into a lawsuit. Then, small claims may be the way to go, though a small claims court can't grant injunctions.