Tex. Tax Code § 24.39: IMPOSITION OF TAX.

The county assessor-collector and commissioners court may not change the apportioned values certified as provided by this subchapter. The county assessor-collector shall add each owner's rolling stock and the value apportioned to the county as certified to him to the appraisal roll certified to him by the chief appraiser as provided by Section 26.01 of this code for county tax purposes. He shall calculate the county tax due on the rolling stock as provided by Section 26.09 of this code.

Acts 1979, 66th Leg., p. 2268, ch. 841, Sec. 1, eff. Jan. 1, 1980. Amended by Acts 1981, 67th Leg., 1st C.S., p. 155, ch. 13, Sec. 94, eff. Aug. 14, 1981; Acts 1983, 68th Leg., p. 4825, ch. 851, Sec. 16, eff. Aug. 29, 1983.