For years they have been every gardener's nightmare - and now farmers fear a plague of moles could spread across the West Midlands countryside because of new legislation from Europe.
From next year, the Government will ban the use of strychnine, a chemical used by farmers to kill off moles, and farmers claim as a result the animals will be able to devastate acres of pasture.
The decision, which comes as a result of an EU directive, has prompted fear among farmers who believe that without the poison they will no longer be able to stop the pest from getting out of control.
Jo Hilditch, who farms and runs luxury holiday lets near Leominster in Herefordshire, said: "Our pest control company has warned us that when strychnine disappears we will be faced with serious mole problems as there is no other financially-viable route for elimination of this pest.
"In the past, when supplies have been short and we have had to wait for long periods of time until the product was available, the problem became well nigh unbearable in our permanent pasture."
The Country Land and Business Association said the British countryside was a breeding ground for moles and the UK needed to retain the use of strychnine as an effective method of pest control.
Moles can be controlled in gardens and amenity grounds by other means, but at field-scale level strychnine is an important tool which should be maintained for use in appropriate and limited circumstances, in accordance with the existing Defra licensing regime, Ms Hilditch said.
Donna Tavernor, regional advisor for the CLA West Midlands, said: "I understand that strychnine is a very effective poison with which to control moles.
"If so, we will be in for an explosion of moles and this will be particularly detrimental for livestock farmers."
Ms Tavernor said the mole hills contaminated silage collected from fields, and this could lead to livestock deaths.
She added: " Criminals will use any means to hand, and simply withdrawing an important and useful land management tool will not, in our view, reduce the impact of criminal activities."
A spokesman for Defra said the ban would come into force on September 1 next year and follows an EU directive.