I believe it is anything 16 inches or over, but that is my personal goal for a trophy to mount, I may not put it on the wall even then because,,... I also believe it could be much smaller in size,,... for there may be a greater reason for a certain fish to be mounted,,... as in a personal experience of being who you were with, or the day, or the place. I have caught a 16"-er but thought the egg laden female would be better if it could still serve the small lake I was fishing in so,,... so gave it back for seed.
To each his, or her own, when it comes to the size of a trophy CRAPPIE. Good luck on all the personal goals for a trophy CRAPPIE!
I believe also that sometimes, it's only in the trying, and fishing, with no catching at all, and one can only hang that, on the memory bank of a heart to rely on,,... for any possible, rainy days, down the road! Ahhhh, remember when....