At this time of the year, cattle producers are selecting and feeding replacement heifers. SDSU Extension Cow/Calf Specialist Taylor Grussing says selection should be based on age and phenotype. “The oldest heifers are most likely to reach puberty earlier and subsequently get bred earlier. I recommend making a list of the oldest 25 percent of the heifers and then evaluate those females phenotypically as well.” From there, Grussing says producers should then determine the number of heifers to be kept. “Keeping about 30 percent of the heifers in the weaning pen is a good place to start. Then, those heifers should be put on a different plane of nutrition.” SDSU Extension will host a Heifer Development Conference on December 6 in Aberdeen.