: : : So surely this means Orcs weren't as good as men when it came to fighting - or maybe it was just sarumans Orcs - perhaps he got them at a Baradur second hand troop sale...

: : While I have no numbers at my fingertips, keep in mind that the Riders of Rohan were on horseback, which tends to be a major advantage over foot troops.

: : -RobRoy

: Exactly. I do not find it difficult to believe that 100 cavalrymen could easily defeat a force three times their size but who were on foot, especially if the force had no pikes or halberds. I don't remember exactly, but it seems to me that orcs used shortswords, for the most part, which are effective in close hand-tohand combat, but virtually useless against cavalry.
: -Olorin

Didn't a good number Eomer's men also have bows? A moving mounted bowmen is very effective against foot troops, even if those some of those troops have bows. Also, these orcs had prisoners. Prisoners that needed to be kept and protected.If the orcs took a defensive position,I think they did, they would be little more than a big target for bowmen, mounted or otherwise.