One of my deer last year that I thought was a doe when I shot turned out to be a button buck. Here in Iowa we don't get 'doe' tags, we get 'antlerless' tags. Antlerless is defined as anything without a forked antler. So, even a 7 inch spike would be considered 'antlerless'. That said, they are very well fed here and I haven't seen one with much over about 4" that isn't forked. We have so many, I won't hesitate to take a spike if it's the only one in sight, but if it is next to a doe, goodbye doe.

Last year's Iowa deer harvest:
Does: 75,073
Antlered Bucks: 52,134
Button Bucks: 16,846
Shed Antler Bucks: 2,161