Question on traps

I have a few questions about traps that I was hoping the Rangers out there could help me with. First, what do the traps look like once they are put down? I'm assuming that allies will not set them off, but can enemies see them very clearly or at all? Also, what sort of range do they have for the trigger? Or in other words, how close does the enemy have to be to them to set them off? And finally, about how big is the area of effect on them once they are set off and does that area differ per trap type? Thanks.

I havent seen anything when i set my traps, but a little effect comes up when someone triggers them (comes within the medium sized range). its not that huge of an effect, but i find it to be quite usefull... not to mention fun to watch them go into my trap and become crippled + bleed so i can run off.

oh yea... don't try to set them if someone is attacking you ^.^ it gets interupted a bit easier then what i thought they would mean by saying "easily interupted".