California Code, Government Code - GOV § 51091

If either the landowner or the county, city, or nonprofit organization desires in any year not to renew the open-space easement, that party shall serve written notice of nonrenewal of the easement upon the other party at least 90 days in advance of the annual renewal date of the open-space easement. Unless such written notice is served at least 90 days in advance of the renewal date, the open-space easement shall be considered renewed as provided in Section 51081.

Upon receipt by the owner of a notice from the county, city, or nonprofit organization of nonrenewal, the owner may make a written protest of the notice of nonrenewal. The county, city, or nonprofit organization may, at any time prior to the renewal date, withdraw the notice of nonrenewal.