I have killed several deer but I don't always know the correct age. I know the teeth, whitehair on face, and bodysize. I just would like to findway of tell more of the right age.

Called checking it it >.< Here they have DNRs at the check in station. They stick a bar in their mouth and tells you how old they are.

Aging A Whitetail Deer

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Not every state has check stations. Here in Illinois this year they got rid of all the check stations except a couple where they were testing for CWD.

IT's done by evaluating the teeth wear. That's why the gums are cut in the rear sides of the mouth, the spreader bar is inserted to open the mouth widely (enough) to clearly see the lower rear teeth and their wear.