Certain regions of the United States, such as New England and the Midwest, are notorious for their harsh winters. During winter, the ground beneath dirt roads and other trails becomes frozen solid, then covered with layers of snow. Sometime during late winter or early spring, the snow and top layer of ground begins to melt, but the water cannot penetrate the still-frozen subsurface. The result is a very muddy mess that creates deep ruts in the roads. This time of the year is known as the fifth season, or mud season.
Of all the regions to suffer through the phenomenon every year, perhaps the state of Vermont has embraced the idea of mud season the most. Local residents of popular winter destinations such as ski resorts know that most tourists avoid the area during the unofficial mud season between March and late April. Residents also know their regular vehicles will not be able to negotiate the deep muddy ruts, so they will often carpool in four-wheel-drive vehicles or switch to off-road vehicles reinforced with tire chains.
Additional rain or a late accumulation of new snow will only help to extend the mud season. Until the deeper layers of ground thaw completely, the run-off from melting snow will continue to mix with the thawed surface dirt. This wet mud is very soft and unforgiving if a car's tires begin to sink in it. Even seasoned towing services can be very reluctant to attempt an extraction during mud season, since the tow truck may also become hopelessly mired in the muck.
Although the thought of making a risky drive through deep muddy ruts is not very appealing, some local residents still enjoy the relative peace and quiet provided by the mud season. Horse trails and public hiking trails may also be closed during mud season, since hikers and horses may also find themselves trapped in deep mud and snow with a consistency of wet concrete. The reduced traffic during mud seasons also allows some local residents the opportunity to drive their off-road vehicles through the deep ruts and puddles strictly for recreation.