California Code, Government Code - GOV § 65250

(a) A city with a population in excess of three million may establish a Long Range Planning Trust Fund in accordance with subdivision (b) to consist of those moneys that are voluntarily paid by an assessee of real property on the property tax bill in an amount equal to one dollar ($1) for each parcel of assessed real property of one acre or less, or one dollar ($1) per acre, and any additional fractional portion thereof, for each parcel of assessed real property of more than one acre, and are collected and deposited pursuant to an agreement as described in subdivision (d).

(b) A city as described in subdivision (a) shall establish a Long Range Planning Trust Fund by a resolution, adopted by a majority vote of the city's governing body.  That resolution shall require that moneys in the fund shall be expended upon the vote of that city's governing body only for purposes of long-term land use planning and general plan revisions.

(c) Upon adoption of a resolution pursuant to subdivision (b), a city may solicit voluntary contributions as described in subdivision (a), and upon receiving authorization to collect a contribution by an assessee of real property, may transmit to the county assessor, county auditor, and county tax collector any information regarding the assessee that may be necessary to collect the contribution pursuant to an agreement as specified in subdivision (d).

(d) The county assessor, county auditor, county tax collector and the adopting city may enter into a joint agreement for the collection and allocation of voluntary contributions as described in subdivision (a), that may provide for the collection of contributions by the tax collector.  The agreement shall provide for the allocation to the county assessor, county auditor, and tax collector from moneys collected of amounts equal to the actual and reasonable costs incurred by those persons in collecting and allocating contributions.