Bananners

That is a nanner, which is basically a pollen sac without the sac. Tightly tie a plastic bag around it. You'll probably have to tie a stem or two in there also. Then remove the plant. From there you can carefully attempt to cut it off. Wait a few hours before putting it back with the rest of your plants. You're better off keeping it segregated for the rest of your grow or even killing it if you have lots of other plants.