This is my 1st year leasinga particular farm herein Illinois. Around the property, I have found a couple tree stands hung in pretty nice spots. I am trying to determine if these were hung previous to this year, or if they're newly hung (and therefore possibly being used when I'm not around). The bark on these mature oak trees has grown around the screw-in steps, roughly 3-4 centimeters growth total. My question is: How long does it take for the tree bark to show signigficant visible growth around steps and chains? Thanks guys.