Worms

Worms are fiercely territorial and, on average, will patrol 6 cubic miles of soil. If you have more than one worm in your garden, it will most likely be the same worm. Worms travel at speeds of 70kmh on average to keep their patch of territory (or as worms know it "turf") protected.
Worms are so protective over their land, they have been know to kill other worms in their sleep.
The worst thing is, you cannot kill them by cutting them up, you just end up creating more of the same worm.

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