Molehill

For the hill in Virginia, see Mole Hill (Virginia).

A molehill

Several lines of molehills

Trail of molehill at Kasori-shell midden, Chiba city, Japan (2008 October, 13)

A molehill (or mole-hill, mole mound) is a conical mound of loose soil raised by small burrowing mammals, including moles, but also similar animals such as mole-rats, marsupial moles and voles. They are often the only sign to indicate the presence of the animal.

Molehills are waste material from digging or repairing burrows, and so are usually found where the animal is establishing new burrows, or where existing ones are damaged (for example by the weight of grazing livestock). Where moles burrow beneath the roots of trees or shrubs, the roots support the tunnel, and molehills are less common, and so even a dense population of the animals may be inconspicuous in these places.

Molehills commonly occur in lines along the route of the burrow, but in some cases they may not be directly above the burrow itself but at the ends of short side-tunnels.

Molehills are sometimes used as a source of fine soil for use in gardening. Particularly they are valued by some practicians of permaculture for the fine potting soil produced by the moles' claws.

Molehills have an important benefit to soil by aerating and tilling it, adding to its fertility.^[1] However, they may cause damage to gardens and areas of grass (such as golf courses), and represent a minor safety hazard.

A notable victim was William III of England, who died in 1702 from pneumonia. This was a complication arising from a broken collarbone after he fell from his horse when it tripped on a molehill. Such accidents are rare.

Where mole-hills are not desired, the moles may be killed, or the fresh molehills may be removed carefully as soon as they appear. This leaves the animals and their galleries undamaged and thus reduces the need for the moles to make further molehills when they clear earth out of the tunnels.

Recording molehills could indicate the number of moles in an area.^[2]

References

1. ^ Parkhurst, Jim. "Managing Wildlife Damage: Moles". Virginia Cooperative Extension. http://www.ext.vt.edu/pubs/wildlife/420-201/420-201.html. Retrieved August 13, 2008. 
2. ^ news.bbc.co.uk