Both actually. We're in zone 7A. Spring is our best grass growing season. It also aligns best for butchering for grass fed beef, allowing harvest around 26-30 months with only two winter feedings required and finishing on grass, not hay for optimal beef quality.

Makes a lot of sense. We are still trying to figure out our system. We've only been at our place for a year but we have very dry summers with no grass growth. Pasture comes back in the winter. I'm thinking our best calving time might be end of winter. We are playing with our options. I hadn't factored in kill dates. That's definitely something id like to properly plan for too.