Will hereford cow calve a limousin calf?

No. A Hereford cow will only give birth to a Hereford-Limousin cross calf if bred to a Limousin bull. Only a Limousin cow can give birth to a Limousin calf--IF she's bred to a Limousin bull. Just like a Hereford cow can only give birth to a Hereford calf if bred to a Hereford bull. Otherwise, she too (referring to the Limousin cow) can give birth to Hereford-Limousin-cross calf if bred to a Hereford bull.