Among other things, a practice must be performed by a farmer or on a farm in order to come within the secondary portion of the definition of ``agriculture.'' No precise lines can be drawn which will serve to delimit the term ``farmer'' in all cases. Essentially, however, the term is an occupational title and the employer must be engaged in activities of a type and to the extent that the person ordinarily regarded as a ``farmer'' is engaged in order to qualify for the title. If this test is met, it is immaterial for what purpose he engages in farming or whether farming is his sole occupation. Thus, an employer's status as a ``farmer'' is not altered by the fact that his only purpose is to obtain products useful to him in a non-farming enterprise which he conducts. For example, an employer engaged in raising nursery stock is a ``farmer'' for purposes of section 3(f) even though his purpose is to supply goods for a separate establishment where he engages in the retail distribution of nursery products. The term ``farmer'' as used in section 3(f) is not confined to individual persons. Thus an association, a partnership, or a corporation which engages in actual farming operations may be a ``farmer'' (see Mitchell v. Budd, 350 U.S. 473). This is so even where it operates ``what might be called the agricultural analogue of the modern industrial assembly line'' (Maneja v. Waialua, 349 U.S. 254).