Noting says MUD like brown wet earth. Every season has pro's and con's. Spring rains keep me from driving my skid loader (tire machine). I slip - I slide - I sink - I make a mess - I get stuck!
After thinking about this problem I came up with a solution. Some will use plywood. The problem with plywood - it breaks, it soaks up water and can be a one time use product?! A 4x8 3/4 Fir CDX treated plywood sheet runs about $40. The next sure thing many big trucks us are the DuraDeck. A 4x8 holds up to 2000 pounds only cost $235 each mat - OUCH! At this price I decided to make the purchase of Stall Mats 4x6 3/4 rubber weigh about 100 pounds. Cost around $35-40 bucks. They do flex when you drive on them and can some times spin out. The Stall mats offer a simple fix. Clearly the DuraDeck or a skid loader with tracks @ $50,000. Are the BEST solutions for mud. I'm ok with my $500 investment.
The best part you can use them over and over. Just hosing them off when your done. Pile them on a pallet to move from job to job. I found they also work great for protecting area's I'm dumping stone matteral. I can place them on top of concrete or asphalt to protect surfaces from handling stones. I also found just keeping them close to the job keeps me from having to trample in mud all day. Or just keeping me safe from slipping and hurting myself. I also love using them to put my stones down on to trim. Easy clean up with the stone chips and durable enough to handle any hammer blows.