all the spear type pole arms, except shortened spear
To my knowledge that is it.
Wrong. Normal spear also doesn't rear horses as Digglez mentioned.
I'm sure I made a list somewhere but can't be assed to look it up so here are the ones I remember and that is CONFIRMED to rear horses. Tell me and I'll check them out and add them to the list.
Here we go:
Scythe, boar spear, bamboo spear, military fork, light lance, ashwood pike, lance, pike, long spear, red tassel spear, war spear, battle fork, swiss halberd, awlpike, long awlpike, heavy lance, english bill, glaive and ALL poleaxes.
Unsure about, but believe to rear horses:
Trident, pitch fork, practice lance, normal/quarter/iron staff, long bardiche, double sided lance and great long bardiche.
Personally I find it ridiculous that the normal "spear" can't rear horses and it's STILL 2 slots. I say either make it rear horses or 1 slot. Maybe 1 slot since the red tassel/war spear already cover the 2 slot spear that can rear horses.
I also prompt to remove rearing of horses on all polearms except: all spears, any stab-only/stab&overhead-only polearms, scythe, poleaxes, forks, trident and lances. Weapons like the glaive/lhb/bardiches shouldn't be able to rear horses. ESPECIALLY the staffs.