(a) Agricultural trade or business. (1) An agricultural trade or business is one in which, if the trade or business were carried on exclusively by employees, the major portion of the services would constitute agricultural labor as defined in section 3121(g) and the regulations thereunder in part 31 of this chapter (Employment Tax Regulations). In case the services are in part agricultural and in part nonagricultural, the time devoted to the performance of each type of service is the test to be used to determine whether the major portion of the services would constitute agricultural labor. If more than half of the time spent in performing all the services is spent in performing services which would constitute agricultural labor under section 3121(g), the trade or business is agricultural. If only half, or less, of the time spent in performing all the services is spent in performing services which would constitute agricultural labor under section 3121(g), the trade or business is not agricultural. In every case the time spent in performing the services will be computed by adding the time spent in the trade or business during the taxable year by every individual (including the individual carrying on such trade or business and the members of his family) in performing such services. The operation of this special rule is not affected by section 3121(c), relating to the included-excluded rule for determining employment.

(2) The rules prescribed in subparagraph (1) of this paragraph have no application where the nonagricultural services are performed in connection with an enterprise which constitutes a trade or business separate and distinct from the trade or business conducted as an agricultural enterprise. Thus, the operation of a roadside automobile service station on farm premises constitutes a trade or business separate and distinct from the agricultural enterprise, and the gross income derived from such service station, less the deductions attributable thereto, is to be taken into account in determining net earnings from self-employment.

(b) Farm operator's income for taxable years ending before 1955. Income derived in a taxable year ending before 1955 from any agricultural trade or business (see paragraph (a) of this section), and all deductions attributable to such income, are excluded in computing net earnings from self-employment.

(c) Farm operator's income for taxable years ending after 1954. Income derived in a taxable year ending after 1954 from an agricultural trade or business (see paragraph (a) of this section) is includible in computing net earnings from self-employment. Income derived from an agricultural trade or business includes income derived by an individual under an agreement entered into by such individual with another person pursuant to which such individual undertakes to produce agricultural or horticultural commodities (including livestock, bees, poultry, and fur-bearing animals and wildlife) on land owned or leased by such other person and pursuant to which the agricultural or horticultural commodities produced by such individual, or the proceeds therefrom, are to be divided between such individual and such other person, and the amount of such individual's share depends on the amount of the agricultural or horticultural commodities produced. However, except as provided in paragraph (d) of this section, relating to arrangements involving material participation, the income derived under such an agreement by the owner or lessee of the land is not includible in computing net earnings from self-employment. See § 1.1402(a)-4. For options relating to the computation of net earnings from self-employment, see §§ 1.1402(a)-14 and 1.1402(a)-15.

(d) Includible farm rental income for taxable years ending after 1955. For taxable years ending after 1955, income derived from an agricultural trade or business (see paragraph (a) of this section) includes also income derived by the owner or tenant of land under an arrangement between such owner or tenant and another person, if such arrangement provides that such other person shall produce agricultural or horticultural commodities (including livestock, bees, poultry, and fur-bearing animals and wildlife) on such land, and that there shall be material participation by the owner or tenant in the production or the management of the production of such agricultural or horticultural commodities, and if there is material participation by the owner or tenant with respect to any such agricultural or horticultural commodity. See paragraph (b) of § 1.1402(a)-4. For options relating to the computation of net earnings from self-employment, see §§ 1.1402(a)-14 and 1.1402(a)-15.

(e) Income from service performed after 1956 as a crew leader. Income derived by a crew leader (see section 3121(o) and the regulations thereunder in Part 31 of this chapter (Employment Tax Regulations)) from service performed after 1956 in furnishing individuals to perform agricultural labor for another person and from service performed after 1956 in agricultural labor as a member of the crew is considered to be income derived from a trade or business for purposes of § 1.1402(c)-1. Whether such trade or business is an agricultural trade or business shall be determined by applying the rules set forth in this section.