Any neglected or abandoned plant or crop is a public nuisance in any of the following circumstances:
(a) It is a menace to the agriculture of the county, district, or vicinity because of the existence of any pest, in or on it.
(b) It is a menace to the agriculture of the county, district, or vicinity because of the existence of any other condition than the condition described in subdivision (a).
(c) It is a host plant of, or provides a favorable or likely harbor for, any pest.