Feed shortages caused by  the drought appear to have triggered a new sort of theft on farms in Waikato.

Thieves hitting farms usually target stock or fuel and equipment. But in a new development, farmers in two areas of Waikato have reported raids on their winter feed supplies.

In one case, a wire fence was cut and large bales of wrapped silage were removed. In the other incident, pasture set aside for stock was grazed before the farmer could use it.

Federated Farmers Waikato president Stew Wadey says all farms are under pressure and any supplementary feed is "like gold" at this time.

Mr. Wadey is asking all rural people to keep an eye on neighbouring properties and to report any suspicious behaviour to police.