I've never used polearms, but just picked up a pike from the ground to do something about horses. I found it laughably easy to stop them with one WPF.
So, my question: What's considered the entry-level polearm, just for anti-cav purposes? I don't necessarily want to kill the horse, but some damage would certainly be nice. Should I just go for a spear, or do I really need a pike for the basic thing? Or don't even go as high as a spear, and a simple pitchfork will do?
I don't intend to spend any WPF for polearms or anything, so it's definitely not for melee combat. Just something to counter annoying ponies.