any idea what to do?

We had a slight case of colic so he was rolling in the muddy paddock. (he's better now since the vet has come)

Any ideas on how to get the filth off of him? Don't say bath, because it's in the 40's here and bath season is over.

You can wait for it to dry and then brush it off him?

I usually wait for the mud to dry off, ( I got a paints and white horses lol so im used to this ;) EVERYDAY ! )
So anyways, Do that and than Groom HIM ALL OUT With Lots of Elbow grease lol, use the curry comb first.

It Certainly Gives an Improvement !
In fact, I can show you what MARSHMELLOW LOOKS before and after :)

Thanks to both of you. It's supposed to rain tomorrow so maybe some of it will come off that way. If not, I'll "wax on, wax off" once he's dry.

Haha! I have seen that movie! (The old one, I haven't seen the new one)

Haha, after the rain just hope that he doesn't go roll in the mud again ;)

I would wait for him to dry and brush the mud off with a stiff brush...the rain may help to get him a little cleaner too. Perhaps a bottle of Miracle Groom would also help for the more stubborn stains. I use that on my Paint in the winter when he gets too dirty and bathing isnt an option.
I am glad that he is feeling better , colic can be kinda scarey IMO ....gotta love those Paints : )

A bottle? A bottle? Maybe a case! Lol

Well as soon as you get him cleaned up throw a blanket on him so we don't have a repeat!!

Perhaps they will give you a discount if you buy a case ...lol