I love running the single track trails in the ice and snow. I like them better on a nice dry spring day when I can wear shorts and a t-shirt more but that doesn’t mean that the trails aren’t great in the winter as well. Winter trail conditions are great when temperatures are consistently at least a few degrees below zero and the precipitation isn’t too heavy. A big snow will generally mean waiting a day or two for some of the swell and brave mountain bikers with the fat tires to blaze a path for us runners, though I have gone out during and after a big snow and enjoyed the run immensely.
Mud – The warm weather recently has made the trail conditions pretty tough. Even the sandier trails down by the river are muddy and running on them will not only provide a mucky slow run but also harm the trails both long term and short term. The inevitable freeze will come and your big muddy footprints will harden like concrete. As well, the efforts by anyone on the trails to avoid the muddiest bits will result in trail degradation.
Ice – Ice on the trails has a different effect then on the roads or pavement. The trails twist and turn and are sloped as well as pretty much always providing a downhill or uphill gradient to challenge you. Just as you pick up speed you will have to negotiate a sharp turn or descend a steep hill which is so much quicker with the frozen stuff on it. Braking can be tough and too much momentum can result in some spectacular wipe outs. I know, oh I know.
Footing is everything in winter. The conditions must be right and the trails are far more fickle. Running in the woods on a snowy evening can be a awesome but it is more of a treat, a frozen treat, then an every day thing.