Now that fruit trees are going dormant you may think that there are no tree fruit chores to be done right now. However, if you have grasses and weeds around the tree you might want to consider a little vegetation management. Even though the weeds are not competing with the tree during the winter for water and nutrients, there are advantages to having bare ground under the tree.
One of the biggest advantages of bare ground is vole control. Voles are mouse like animals with short tails and small ears. Pine voles are subterranean, but are different from moles in that they do not push up the soil when they tunnel. Instead the ground feels spongy, especially if you have a large population.
Pine voles can be very destructive in that they will strip off all of the bark on the trunk below the soil line (top picture). The next season, the tree may leaf out alright, but slowly decline as the season progresses (bottom picture). This girdling will eventually kill the tree. Having bear ground exposes the tunnel to natural predators, like snakes, foxes, dogs, and cats. Voles also love mulch, so you may want to pull the mulch back to check for the vole activity.
Another advantage of having bare ground is frost protection in the spring. Studies have shown that bare, wet ground absorbs more heat then soil covered with weeds or mulch. This soil releases the heat at night and can raise the temperature in the tree by a couple of degrees (not much, but a couple of degrees can mean the difference between having fruit and having no crop).