This Act empowers the Minister to declare any plant to be a noxious weed in any area which may be specified in such notice, and may at any time vary or revoke such notice. It shall be the duty of every occupier of land within an area in respect of which any plant has been declared to be a noxious weed under the provisions of section three to notify presence of noxious weeds and to undertake reasonable steps to eradicate such weed. Similar duties are imposed on Rural Councils. Other provisions of