Temporary ones just below the ground surface for feeding, and permanent ones 10-18 inches beneath the surface. A large chamber in the deeper runways is used as a retreat during drought, heat, cold, and as a nest for the young. The digging of the surface tunnels can be up to one foot per minute while in search of food, the underground digging rate is 12 foot per hour. When digging the dirt passes under the mole until a pile has formed. The mole then pushes it through a vertical tunnel and outside thus leaving a molehill on the surface.
Moles live a solitary life only tolerating others during mating season.
Mating occurs in the Spring. After one month, the young are able to care for themselves and reek havoc on your lawn. The balance of their diet include seeds, grass roots, etc. Earthworms are one of their favorites, and although grubs may attract moles to an area, the elimination of grubs will not remove the moles if there are earthworms present, and conversely, the presence of moles is not a sure sign that you have grubs, especially if it has been treated for grubs. Baits are successful if a mole accidentally eats them while searching for food.